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Re: [Qemu-devel] [PATCH v9 2/3] pl330: Initial version


From: Peter Crosthwaite
Subject: Re: [Qemu-devel] [PATCH v9 2/3] pl330: Initial version
Date: Mon, 18 Feb 2013 10:58:32 +1000

Ping!

There are comments on Patches 1 & 3 of this series, but all are out of
scope of this patch. Can I get a review of this patch?

Regards,
Peter

On Fri, Feb 8, 2013 at 1:42 PM, Peter Crosthwaite
<address@hidden> wrote:
> Device model for Primecell PL330 dma controller.
>
> Signed-off-by: Peter Crosthwaite <address@hidden>
> Signed-off-by: Kirill Batuzov <address@hidden>
> Tested-by: Igor Mitsyanko <address@hidden>
> ---
> changed from v9:
> s/sysbus_from_qdev/SYS_BUS_DEVICE (rebase)
> Fixed include names (rebase)
> Reworked debug instrumentation
> Added level 2 debug hexdumper (dumps all transferred data)
> Fixed load<->store queue syncro (ops were happening out of order)
> Fixed barrier ionstructions (return to exec state)
> Fixed misaligned transfer behaviour (implemented transfer boundary truncation)
> Fixed compile time warning in printfs
> Added several DB_PRINT to track instruction execution
> changed from v8:
> Set default values of parameters to match Xilinx Zynq PL330
> changed from v7:
> fixed dmawfe logic. All waiting threads will unlock on dmasev, rather than one
> changed from v6:
> fixed data_width hw_error args (Igor review)
> changed from v5:
> s/cpu_physical_memory_foo/dma_memory_foo (PMM review)
> remove casts of g_new/malloc (PMM review)
> s/hw_error/qemu_log_mask for registers read/write errors (PMM review)
> set allowable access size to 4 (saves on a qemu_log)
> fixed is_manager = 1 (s/1/true) (PMM Review)
> decoded data_width prop instead of use directly as field in CRD (Igor review)
>         Makes code more consistent with other properties
> changed from v4:
> Some Makefile refactoring updates
> refactored properties to match primecell options rather than be the config
> register values (PMM review)
> s/chanel/channel (PMM review)
> elaborated names of single letter fields of PL330FIFO (PMM review)
> remove use of target_phys_addr_t (PMM review)
> "Put instruction to queue" - fixed comment style (PMM review)
> changed dmago non-manager usage to throw PL330_FAULT_UNDEF (Igor Review)
> Added VMSD (PMM review)
> Changed version to r01p01 (PMM Review)
> const'ified TypeInfo (Igor review)
> changed from v3:
> rebased against Makefile refactor
> changed from v2 (in order of diff appearance):
> GPL version changed to v2 or later
> Register and field names changed to match TRM
> id field corrected
> PL330ChanState enum corrected
> target_phys_addr_t usages removed
> identifier camel casing and underscoring fixed
> data fifo reworked (uses head ptr and a occupancy count rather than head & 
> tail ptrs)
> pl330_insn_from_queue->pl330_queue_remove_insn
> Numerous typos in comments corrected as per review
> g_malloc0(sizeof(a) * b) -> g_new
> pl330_fifo_inc: changed to accept PL330Fifo struct as argument (rather than 
> buf_size)
> pl330_fifo_push/get: rollback on overflow mechanism replaced with pre-check
> pl330_queue_find_insn: fixed ugly if statement whitespace (PMM review)
> pl330_dmaaddh: fixed arugment reversal
> pl330_dmaaddh: asserted on !manager
> "ns": change to be and behave like a boolean globally
> pl330_dmald: force num=1 when PL330_SINGLE
> pl330_dma_kill: put in correct alphabet order
> pl330_dmarmb/wmb:implemented
> pl330_exec_insn: asserted insn->size not too big
> pl330_exec_insn: enabled stall mechanism outside exec state (needed for 
> rmb/wmb)
> pl330_debug_exec: assert fault type on a fault
> pl330_iomem_write: removed aligmnent assertion
> pl330_iomem_write: corrected ev_status and irq_status logic
> pl330_iomem_read_imp: fixed some incorrect bitfield positions (PMM review)
> pl330_reset: stopped timer
> pl330_init: removed redundant reset
> changed from v1:
> GPLv2 license
> some code formatting fixes
>
>  default-configs/arm-softmmu.mak |    1 +
>  hw/Makefile.objs                |    1 +
>  hw/pl330.c                      | 1645 
> +++++++++++++++++++++++++++++++++++++++
>  3 files changed, 1647 insertions(+), 0 deletions(-)
>  create mode 100644 hw/pl330.c
>
> diff --git a/default-configs/arm-softmmu.mak b/default-configs/arm-softmmu.mak
> index 2f1a5c9..1775455 100644
> --- a/default-configs/arm-softmmu.mak
> +++ b/default-configs/arm-softmmu.mak
> @@ -41,6 +41,7 @@ CONFIG_PL110=y
>  CONFIG_PL181=y
>  CONFIG_PL190=y
>  CONFIG_PL310=y
> +CONFIG_PL330=y
>  CONFIG_CADENCE=y
>  CONFIG_XGMAC=y
>
> diff --git a/hw/Makefile.objs b/hw/Makefile.objs
> index 447e32a..39f7f84 100644
> --- a/hw/Makefile.objs
> +++ b/hw/Makefile.objs
> @@ -96,6 +96,7 @@ common-obj-$(CONFIG_PL110) += pl110.o
>  common-obj-$(CONFIG_PL181) += pl181.o
>  common-obj-$(CONFIG_PL190) += pl190.o
>  common-obj-$(CONFIG_PL310) += arm_l2x0.o
> +common-obj-$(CONFIG_PL330) += pl330.o
>  common-obj-$(CONFIG_VERSATILE_PCI) += versatile_pci.o
>  common-obj-$(CONFIG_VERSATILE_I2C) += versatile_i2c.o
>  common-obj-$(CONFIG_CADENCE) += cadence_uart.o
> diff --git a/hw/pl330.c b/hw/pl330.c
> new file mode 100644
> index 0000000..81e04da
> --- /dev/null
> +++ b/hw/pl330.c
> @@ -0,0 +1,1645 @@
> +/*
> + * ARM PrimeCell PL330 DMA Controller
> + *
> + * Copyright (c) 2009 Samsung Electronics.
> + * Contributed by Kirill Batuzov <address@hidden>
> + * Copyright (c) 2012 Peter A.G. Crosthwaite (address@hidden)
> + * Copyright (c) 2012 PetaLogix Pty Ltd.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; version 2 or later.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include "sysbus.h"
> +#include "qemu/timer.h"
> +#include "qemu/hexdump.h"
> +#include "sysemu/dma.h"
> +
> +#ifndef PL330_ERR_DEBUG
> +#define PL330_ERR_DEBUG 0
> +#endif
> +
> +#define DB_PRINT_L(lvl, fmt, args...) do {\
> +    if (PL330_ERR_DEBUG >= lvl) {\
> +        fprintf(stderr, "PL330: %s:" fmt, __func__, ## args);\
> +    } \
> +} while (0);
> +
> +#define DB_PRINT(fmt, args...) DB_PRINT_L(1, fmt, ## args)
> +
> +#define PL330_PERIPH_NUM            32
> +#define PL330_MAX_BURST_LEN         128
> +#define PL330_INSN_MAXSIZE          6
> +
> +#define PL330_FIFO_OK               0
> +#define PL330_FIFO_STALL            1
> +#define PL330_FIFO_ERR              (-1)
> +
> +#define PL330_FAULT_UNDEF_INSTR             (1 <<  0)
> +#define PL330_FAULT_OPERAND_INVALID         (1 <<  1)
> +#define PL330_FAULT_DMAGO_ERR               (1 <<  4)
> +#define PL330_FAULT_EVENT_ERR               (1 <<  5)
> +#define PL330_FAULT_CH_PERIPH_ERR           (1 <<  6)
> +#define PL330_FAULT_CH_RDWR_ERR             (1 <<  7)
> +#define PL330_FAULT_ST_DATA_UNAVAILABLE     (1 << 12)
> +#define PL330_FAULT_FIFOEMPTY_ERR           (1 << 13)
> +#define PL330_FAULT_INSTR_FETCH_ERR         (1 << 16)
> +#define PL330_FAULT_DATA_WRITE_ERR          (1 << 17)
> +#define PL330_FAULT_DATA_READ_ERR           (1 << 18)
> +#define PL330_FAULT_DBG_INSTR               (1 << 30)
> +#define PL330_FAULT_LOCKUP_ERR              (1 << 31)
> +
> +#define PL330_UNTAGGED              0xff
> +
> +#define PL330_SINGLE                0x0
> +#define PL330_BURST                 0x1
> +
> +#define PL330_WATCHDOG_LIMIT        1024
> +
> +/* IOMEM mapped registers */
> +#define PL330_REG_DSR               0x000
> +#define PL330_REG_DPC               0x004
> +#define PL330_REG_INTEN             0x020
> +#define PL330_REG_INT_EVENT_RIS     0x024
> +#define PL330_REG_INTMIS            0x028
> +#define PL330_REG_INTCLR            0x02C
> +#define PL330_REG_FSRD              0x030
> +#define PL330_REG_FSRC              0x034
> +#define PL330_REG_FTRD              0x038
> +#define PL330_REG_FTR_BASE          0x040
> +#define PL330_REG_CSR_BASE          0x100
> +#define PL330_REG_CPC_BASE          0x104
> +#define PL330_REG_CHANCTRL          0x400
> +#define PL330_REG_DBGSTATUS         0xD00
> +#define PL330_REG_DBGCMD            0xD04
> +#define PL330_REG_DBGINST0          0xD08
> +#define PL330_REG_DBGINST1          0xD0C
> +#define PL330_REG_CR0_BASE          0xE00
> +#define PL330_REG_PERIPH_ID         0xFE0
> +
> +#define PL330_IOMEM_SIZE    0x1000
> +
> +#define CFG_BOOT_ADDR 2
> +#define CFG_INS 3
> +#define CFG_PNS 4
> +#define CFG_CRD 5
> +
> +static const uint32_t pl330_id[] = {
> +    0x30, 0x13, 0x24, 0x00, 0x0D, 0xF0, 0x05, 0xB1
> +};
> +
> +/* DMA channel states as they are described in PL330 Technical Reference 
> Manual
> + * Most of them will not be used in emulation.
> + */
> +typedef enum  {
> +    pl330_chan_stopped = 0,
> +    pl330_chan_executing = 1,
> +    pl330_chan_cache_miss = 2,
> +    pl330_chan_updating_pc = 3,
> +    pl330_chan_waiting_event = 4,
> +    pl330_chan_at_barrier = 5,
> +    pl330_chan_queue_busy = 6,
> +    pl330_chan_waiting_periph = 7,
> +    pl330_chan_killing = 8,
> +    pl330_chan_completing = 9,
> +    pl330_chan_fault_completing = 14,
> +    pl330_chan_fault = 15,
> +} PL330ChanState;
> +
> +typedef struct PL330 PL330;
> +
> +typedef struct PL330Chan {
> +    uint32_t src;
> +    uint32_t dst;
> +    uint32_t pc;
> +    uint32_t control;
> +    uint32_t status;
> +    uint32_t lc[2];
> +    uint32_t fault_type;
> +    uint32_t watchdog_timer;
> +
> +    bool ns;
> +    uint8_t request_flag;
> +    uint8_t wakeup;
> +    uint8_t wfp_sbp;
> +
> +    uint8_t state;
> +    uint8_t stall;
> +
> +    bool is_manager;
> +    PL330 *parent;
> +    uint8_t tag;
> +} PL330Chan;
> +
> +static const VMStateDescription vmstate_pl330_chan = {
> +    .name = "pl330_chan",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .minimum_version_id_old = 1,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT32(src, PL330Chan),
> +        VMSTATE_UINT32(dst, PL330Chan),
> +        VMSTATE_UINT32(pc, PL330Chan),
> +        VMSTATE_UINT32(control, PL330Chan),
> +        VMSTATE_UINT32(status, PL330Chan),
> +        VMSTATE_UINT32_ARRAY(lc, PL330Chan, 2),
> +        VMSTATE_UINT32(fault_type, PL330Chan),
> +        VMSTATE_UINT32(watchdog_timer, PL330Chan),
> +        VMSTATE_BOOL(ns, PL330Chan),
> +        VMSTATE_UINT8(request_flag, PL330Chan),
> +        VMSTATE_UINT8(wakeup, PL330Chan),
> +        VMSTATE_UINT8(wfp_sbp, PL330Chan),
> +        VMSTATE_UINT8(state, PL330Chan),
> +        VMSTATE_UINT8(stall, PL330Chan),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +typedef struct PL330Fifo {
> +    uint8_t *buf;
> +    uint8_t *tag;
> +    uint32_t head;
> +    uint32_t num;
> +    uint32_t buf_size;
> +} PL330Fifo;
> +
> +static const VMStateDescription vmstate_pl330_fifo = {
> +    .name = "pl330_chan",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .minimum_version_id_old = 1,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_VBUFFER_UINT32(buf, PL330Fifo, 1, NULL, 0, buf_size),
> +        VMSTATE_VBUFFER_UINT32(tag, PL330Fifo, 1, NULL, 0, buf_size),
> +        VMSTATE_UINT32(head, PL330Fifo),
> +        VMSTATE_UINT32(num, PL330Fifo),
> +        VMSTATE_UINT32(buf_size, PL330Fifo),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +typedef struct PL330QueueEntry {
> +    uint32_t addr;
> +    uint32_t len;
> +    uint8_t n;
> +    bool inc;
> +    bool z;
> +    uint8_t tag;
> +    uint8_t seqn;
> +} PL330QueueEntry;
> +
> +static const VMStateDescription vmstate_pl330_queue_entry = {
> +    .name = "pl330_queue_entry",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .minimum_version_id_old = 1,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT32(addr, PL330QueueEntry),
> +        VMSTATE_UINT32(len, PL330QueueEntry),
> +        VMSTATE_UINT8(n, PL330QueueEntry),
> +        VMSTATE_BOOL(inc, PL330QueueEntry),
> +        VMSTATE_BOOL(z, PL330QueueEntry),
> +        VMSTATE_UINT8(tag, PL330QueueEntry),
> +        VMSTATE_UINT8(seqn, PL330QueueEntry),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +typedef struct PL330Queue {
> +    PL330 *parent;
> +    PL330QueueEntry *queue;
> +    uint32_t queue_size;
> +} PL330Queue;
> +
> +static const VMStateDescription vmstate_pl330_queue = {
> +    .name = "pl330_queue",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .minimum_version_id_old = 1,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_STRUCT_VARRAY_UINT32(queue, PL330Queue, queue_size, 1,
> +                                 vmstate_pl330_queue_entry, PL330QueueEntry),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +struct PL330 {
> +    SysBusDevice busdev;
> +    MemoryRegion iomem;
> +    qemu_irq irq_abort;
> +    qemu_irq *irq;
> +
> +    /* Config registers. cfg[5] = CfgDn. */
> +    uint32_t cfg[6];
> +#define EVENT_SEC_STATE 3
> +#define PERIPH_SEC_STATE 4
> +    /* cfg 0 bits and pieces */
> +    uint32_t num_chnls;
> +    uint8_t num_periph_req;
> +    uint8_t num_events;
> +    uint8_t mgr_ns_at_rst;
> +    /* cfg 1 bits and pieces */
> +    uint8_t i_cache_len;
> +    uint8_t num_i_cache_lines;
> +    /* CRD bits and pieces */
> +    uint8_t data_width;
> +    uint8_t wr_cap;
> +    uint8_t wr_q_dep;
> +    uint8_t rd_cap;
> +    uint8_t rd_q_dep;
> +    uint16_t data_buffer_dep;
> +
> +    PL330Chan manager;
> +    PL330Chan *chan;
> +    PL330Fifo fifo;
> +    PL330Queue read_queue;
> +    PL330Queue write_queue;
> +    uint8_t *lo_seqn;
> +    uint8_t *hi_seqn;
> +    QEMUTimer *timer; /* is used for restore dma. */
> +
> +    uint32_t inten;
> +    uint32_t int_status;
> +    uint32_t ev_status;
> +    uint32_t dbg[2];
> +    uint8_t debug_status;
> +    uint8_t num_faulting;
> +    uint8_t periph_busy[PL330_PERIPH_NUM];
> +
> +};
> +
> +static const VMStateDescription vmstate_pl330 = {
> +    .name = "pl330",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .minimum_version_id_old = 1,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_STRUCT(manager, PL330, 0, vmstate_pl330_chan, PL330Chan),
> +        VMSTATE_STRUCT_VARRAY_UINT32(chan, PL330, num_chnls, 0,
> +                                     vmstate_pl330_chan, PL330Chan),
> +        VMSTATE_VBUFFER_UINT32(lo_seqn, PL330, 1, NULL, 0, num_chnls),
> +        VMSTATE_VBUFFER_UINT32(hi_seqn, PL330, 1, NULL, 0, num_chnls),
> +        VMSTATE_STRUCT(fifo, PL330, 0, vmstate_pl330_fifo, PL330Fifo),
> +        VMSTATE_STRUCT(read_queue, PL330, 0, vmstate_pl330_queue, 
> PL330Queue),
> +        VMSTATE_STRUCT(write_queue, PL330, 0, vmstate_pl330_queue, 
> PL330Queue),
> +        VMSTATE_TIMER(timer, PL330),
> +        VMSTATE_UINT32(inten, PL330),
> +        VMSTATE_UINT32(int_status, PL330),
> +        VMSTATE_UINT32(ev_status, PL330),
> +        VMSTATE_UINT32_ARRAY(dbg, PL330, 2),
> +        VMSTATE_UINT8(debug_status, PL330),
> +        VMSTATE_UINT8(num_faulting, PL330),
> +        VMSTATE_UINT8_ARRAY(periph_busy, PL330, PL330_PERIPH_NUM),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +typedef struct PL330InsnDesc {
> +    /* OPCODE of the instruction */
> +    uint8_t opcode;
> +    /* Mask so we can select several sibling instructions, such as
> +       DMALD, DMALDS and DMALDB */
> +    uint8_t opmask;
> +    /* Size of instruction in bytes */
> +    uint8_t size;
> +    /* Interpreter */
> +    void (*exec)(PL330Chan *, uint8_t opcode, uint8_t *args, int len);
> +} PL330InsnDesc;
> +
> +
> +/* MFIFO Implementation
> + *
> + * MFIFO is implemented as a cyclic buffer of BUF_SIZE size. Tagged bytes are
> + * stored in this buffer. Data is stored in BUF field, tags - in the
> + * corresponding array elements of TAG field.
> + */
> +
> +/* Initialize queue. */
> +
> +static void pl330_fifo_init(PL330Fifo *s, uint32_t size)
> +{
> +    s->buf = g_malloc0(size);
> +    s->tag = g_malloc0(size);
> +    s->buf_size = size;
> +}
> +
> +/* Cyclic increment */
> +
> +static inline int pl330_fifo_inc(PL330Fifo *s, int x)
> +{
> +    return (x + 1) % s->buf_size;
> +}
> +
> +/* Number of empty bytes in MFIFO */
> +
> +static inline int pl330_fifo_num_free(PL330Fifo *s)
> +{
> +    return s->buf_size - s->num;
> +}
> +
> +/* Push LEN bytes of data stored in BUF to MFIFO and tag it with TAG.
> + * Zero returned on success, PL330_FIFO_STALL if there is no enough free
> + * space in MFIFO to store requested amount of data. If push was unsuccessful
> + * no data is stored to MFIFO.
> + */
> +
> +static int pl330_fifo_push(PL330Fifo *s, uint8_t *buf, int len, uint8_t tag)
> +{
> +    int i;
> +
> +    if (s->buf_size - s->num < len) {
> +        return PL330_FIFO_STALL;
> +    }
> +    for (i = 0; i < len; i++) {
> +        int push_idx = (s->head + s->num + i) % s->buf_size;
> +        s->buf[push_idx] = buf[i];
> +        s->tag[push_idx] = tag;
> +    }
> +    s->num += len;
> +    return PL330_FIFO_OK;
> +}
> +
> +/* Get LEN bytes of data from MFIFO and store it to BUF. Tag value of each
> + * byte is verified. Zero returned on success, PL330_FIFO_ERR on tag mismatch
> + * and PL330_FIFO_STALL if there is no enough data in MFIFO. If get was
> + * unsuccessful no data is removed from MFIFO.
> + */
> +
> +static int pl330_fifo_get(PL330Fifo *s, uint8_t *buf, int len, uint8_t tag)
> +{
> +    int i;
> +
> +    if (s->num < len) {
> +        return PL330_FIFO_STALL;
> +    }
> +    for (i = 0; i < len; i++) {
> +        if (s->tag[s->head] == tag) {
> +            int get_idx = (s->head + i) % s->buf_size;
> +            buf[i] = s->buf[get_idx];
> +        } else { /* Tag mismatch - Rollback transaction */
> +            return PL330_FIFO_ERR;
> +        }
> +    }
> +    s->head = (s->head + len) % s->buf_size;
> +    s->num -= len;
> +    return PL330_FIFO_OK;
> +}
> +
> +/* Reset MFIFO. This completely erases all data in it. */
> +
> +static inline void pl330_fifo_reset(PL330Fifo *s)
> +{
> +    s->head = 0;
> +    s->num = 0;
> +}
> +
> +/* Return tag of the first byte stored in MFIFO. If MFIFO is empty
> + * PL330_UNTAGGED is returned.
> + */
> +
> +static inline uint8_t pl330_fifo_tag(PL330Fifo *s)
> +{
> +    return (!s->num) ? PL330_UNTAGGED : s->tag[s->head];
> +}
> +
> +/* Returns non-zero if tag TAG is present in fifo or zero otherwise */
> +
> +static int pl330_fifo_has_tag(PL330Fifo *s, uint8_t tag)
> +{
> +    int i, n;
> +
> +    i = s->head;
> +    for (n = 0; n < s->num; n++) {
> +        if (s->tag[i] == tag) {
> +            return 1;
> +        }
> +        i = pl330_fifo_inc(s, i);
> +    }
> +    return 0;
> +}
> +
> +/* Remove all entry tagged with TAG from MFIFO */
> +
> +static void pl330_fifo_tagged_remove(PL330Fifo *s, uint8_t tag)
> +{
> +    int i, t, n;
> +
> +    t = i = s->head;
> +    for (n = 0; n < s->num; n++) {
> +        if (s->tag[i] != tag) {
> +            s->buf[t] = s->buf[i];
> +            s->tag[t] = s->tag[i];
> +            t = pl330_fifo_inc(s, t);
> +        } else {
> +            s->num = s->num - 1;
> +        }
> +        i = pl330_fifo_inc(s, i);
> +    }
> +}
> +
> +/* Read-Write Queue implementation
> + *
> + * A Read-Write Queue stores up to QUEUE_SIZE instructions (loads or stores).
> + * Each instruction is described by source (for loads) or destination (for
> + * stores) address ADDR, width of data to be loaded/stored LEN, number of
> + * stores/loads to be performed N, INC bit, Z bit and TAG to identify channel
> + * this instruction belongs to. Queue does not store any information about
> + * nature of the instruction: is it load or store. PL330 has different queues
> + * for loads and stores so this is already known at the top level where it
> + * matters.
> + *
> + * Queue works as FIFO for instructions with equivalent tags, but can issue
> + * instructions with different tags in arbitrary order. SEQN field attached 
> to
> + * each instruction helps to achieve this. For each TAG queue contains
> + * instructions with consecutive SEQN values ranging from LO_SEQN[TAG] to
> + * HI_SEQN[TAG]-1 inclusive. SEQN is 8-bit unsigned integer, so SEQN=255 is
> + * followed by SEQN=0.
> + *
> + * Z bit indicates that zeroes should be stored. No MFIFO fetches are 
> performed
> + * in this case.
> + */
> +
> +static void pl330_queue_reset(PL330Queue *s)
> +{
> +    int i;
> +
> +    for (i = 0; i < s->queue_size; i++) {
> +        s->queue[i].tag = PL330_UNTAGGED;
> +    }
> +}
> +
> +/* Initialize queue */
> +static void pl330_queue_init(PL330Queue *s, int size, int channum, PL330 
> *parent)
> +{
> +    s->parent = parent;
> +    s->queue = g_new0(PL330QueueEntry, size);
> +    s->queue_size = size;
> +}
> +
> +/* Returns pointer to an empty slot or NULL if queue is full */
> +static PL330QueueEntry *pl330_queue_find_empty(PL330Queue *s)
> +{
> +    int i;
> +
> +    for (i = 0; i < s->queue_size; i++) {
> +        if (s->queue[i].tag == PL330_UNTAGGED) {
> +            return &s->queue[i];
> +        }
> +    }
> +    return NULL;
> +}
> +
> +/* Put instruction to queue.
> + * Return value:
> + * - zero - OK
> + * - non-zero - queue is full
> + */
> +
> +static int pl330_queue_put_insn(PL330Queue *s, uint32_t addr,
> +                               int len, int n, bool inc, bool z, uint8_t tag,
> +                               PL330Chan *c)
> +{
> +    PL330QueueEntry *entry = pl330_queue_find_empty(s);
> +
> +    if (!entry) {
> +        return 1;
> +    }
> +    entry->tag = tag;
> +    entry->addr = addr;
> +    entry->len = len;
> +    entry->n = n;
> +    entry->z = z;
> +    entry->inc = inc;
> +    entry->seqn = s->parent->hi_seqn[tag];
> +    s->parent->hi_seqn[tag]++;
> +    return 0;
> +}
> +
> +/* Returns a pointer to queue slot containing instruction which satisfies
> + *  following conditions:
> + *   - it has valid tag value (not PL330_UNTAGGED)
> + *   - if enforce_seq is set it has to be issuable without violating queue
> + *     logic (see above)
> + *   - if TAG argument is not PL330_UNTAGGED this instruction has tag value
> + *     equivalent to the argument TAG value.
> + *  If such instruction cannot be found NULL is returned.
> + */
> +
> +static PL330QueueEntry *pl330_queue_find_insn(PL330Queue *s, uint8_t tag,
> +                                              bool enforce_seq)
> +{
> +    int i;
> +
> +    for (i = 0; i < s->queue_size; i++) {
> +        if (s->queue[i].tag != PL330_UNTAGGED) {
> +            if ((!enforce_seq ||
> +                    s->queue[i].seqn == s->parent->lo_seqn[s->queue[i].tag]) 
> &&
> +                    (s->queue[i].tag == tag || tag == PL330_UNTAGGED ||
> +                    s->queue[i].z)) {
> +                return &s->queue[i];
> +            }
> +        }
> +    }
> +    return NULL;
> +}
> +
> +/* Removes instruction from queue. */
> +
> +static inline void pl330_queue_remove_insn(PL330Queue *s, PL330QueueEntry *e)
> +{
> +    s->parent->lo_seqn[e->tag]++;
> +    e->tag = PL330_UNTAGGED;
> +}
> +
> +/* Removes all instructions tagged with TAG from queue. */
> +
> +static inline void pl330_queue_remove_tagged(PL330Queue *s, uint8_t tag)
> +{
> +    int i;
> +
> +    for (i = 0; i < s->queue_size; i++) {
> +        if (s->queue[i].tag == tag) {
> +            s->queue[i].tag = PL330_UNTAGGED;
> +        }
> +    }
> +}
> +
> +/* DMA instruction execution engine */
> +
> +/* Moves DMA channel to the FAULT state and updates it's status. */
> +
> +static inline void pl330_fault(PL330Chan *ch, uint32_t flags)
> +{
> +    DB_PRINT("ch: %p, flags: %x\n", ch, flags);
> +    ch->fault_type |= flags;
> +    if (ch->state == pl330_chan_fault) {
> +        return;
> +    }
> +    ch->state = pl330_chan_fault;
> +    ch->parent->num_faulting++;
> +    if (ch->parent->num_faulting == 1) {
> +        DB_PRINT("abort interrupt raised\n");
> +        qemu_irq_raise(ch->parent->irq_abort);
> +    }
> +}
> +
> +/*
> + * For information about instructions see PL330 Technical Reference Manual.
> + *
> + * Arguments:
> + *   CH - channel executing the instruction
> + *   OPCODE - opcode
> + *   ARGS - array of 8-bit arguments
> + *   LEN - number of elements in ARGS array
> + */
> +
> +static void pl330_dmaaddh(PL330Chan *ch, uint8_t opcode, uint8_t *args, int 
> len)
> +{
> +    uint16_t im = (((uint16_t)args[1]) << 8) | ((uint16_t)args[0]);
> +    uint8_t ra = (opcode >> 1) & 1;
> +
> +    if (ch->is_manager) {
> +        pl330_fault(ch, PL330_FAULT_UNDEF_INSTR);
> +        return;
> +    }
> +    if (ra) {
> +        ch->dst += im;
> +    } else {
> +        ch->src += im;
> +    }
> +}
> +
> +static void pl330_dmaend(PL330Chan *ch, uint8_t opcode,
> +                         uint8_t *args, int len)
> +{
> +    PL330 *s = ch->parent;
> +
> +    if (ch->state == pl330_chan_executing && !ch->is_manager) {
> +        /* Wait for all transfers to complete */
> +        if (pl330_fifo_has_tag(&s->fifo, ch->tag) ||
> +            pl330_queue_find_insn(&s->read_queue, ch->tag, false) != NULL ||
> +            pl330_queue_find_insn(&s->write_queue, ch->tag, false) != NULL) {
> +
> +            ch->stall = 1;
> +            return;
> +        }
> +    }
> +    DB_PRINT("DMA ending!\n");
> +    pl330_fifo_tagged_remove(&s->fifo, ch->tag);
> +    pl330_queue_remove_tagged(&s->read_queue, ch->tag);
> +    pl330_queue_remove_tagged(&s->write_queue, ch->tag);
> +    ch->state = pl330_chan_stopped;
> +}
> +
> +static void pl330_dmaflushp(PL330Chan *ch, uint8_t opcode,
> +                                            uint8_t *args, int len)
> +{
> +    uint8_t periph_id;
> +
> +    if (args[0] & 7) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    periph_id = (args[0] >> 3) & 0x1f;
> +    if (periph_id >= ch->parent->num_periph_req) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    if (ch->ns && !(ch->parent->cfg[CFG_PNS] & (1 << periph_id))) {
> +        pl330_fault(ch, PL330_FAULT_CH_PERIPH_ERR);
> +        return;
> +    }
> +    /* Do nothing */
> +}
> +
> +static void pl330_dmago(PL330Chan *ch, uint8_t opcode, uint8_t *args, int 
> len)
> +{
> +    uint8_t chan_id;
> +    uint8_t ns;
> +    uint32_t pc;
> +    PL330Chan *s;
> +
> +    DB_PRINT("\n");
> +
> +    if (!ch->is_manager) {
> +        pl330_fault(ch, PL330_FAULT_UNDEF_INSTR);
> +        return;
> +    }
> +    ns = !!(opcode & 2);
> +    chan_id = args[0] & 7;
> +    if ((args[0] >> 3)) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    if (chan_id >= ch->parent->num_chnls) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    pc = (((uint32_t)args[4]) << 24) | (((uint32_t)args[3]) << 16) |
> +         (((uint32_t)args[2]) << 8)  | (((uint32_t)args[1]));
> +    if (ch->parent->chan[chan_id].state != pl330_chan_stopped) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    if (ch->ns && !ns) {
> +        pl330_fault(ch, PL330_FAULT_DMAGO_ERR);
> +        return;
> +    }
> +    s = &ch->parent->chan[chan_id];
> +    s->ns = ns;
> +    s->pc = pc;
> +    s->state = pl330_chan_executing;
> +}
> +
> +static void pl330_dmald(PL330Chan *ch, uint8_t opcode, uint8_t *args, int 
> len)
> +{
> +    uint8_t bs = opcode & 3;
> +    uint32_t size, num;
> +    bool inc;
> +
> +    if (bs == 2) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    if ((bs == 1 && ch->request_flag == PL330_BURST) ||
> +        (bs == 3 && ch->request_flag == PL330_SINGLE)) {
> +        /* Perform NOP */
> +        return;
> +    }
> +    if (bs == 1 && ch->request_flag == PL330_SINGLE) {
> +        num = 1;
> +    } else {
> +        num = ((ch->control >> 4) & 0xf) + 1;
> +    }
> +    size = (uint32_t)1 << ((ch->control >> 1) & 0x7);
> +    inc = !!(ch->control & 1);
> +    ch->stall = pl330_queue_put_insn(&ch->parent->read_queue, ch->src,
> +                                    size, num, inc, 0, ch->tag, ch);
> +    if (!ch->stall) {
> +        DB_PRINT("channel:%d address:%08x size:%d num:%d %c\n",
> +                 ch->tag, ch->src, size, num, inc ? 'Y' : 'N');
> +        ch->src += inc ? size * num - (ch->src & (size - 1)) : 0;
> +    }
> +}
> +
> +static void pl330_dmaldp(PL330Chan *ch, uint8_t opcode, uint8_t *args, int 
> len)
> +{
> +    uint8_t periph_id;
> +
> +    if (args[0] & 7) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    periph_id = (args[0] >> 3) & 0x1f;
> +    if (periph_id >= ch->parent->num_periph_req) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    if (ch->ns && !(ch->parent->cfg[CFG_PNS] & (1 << periph_id))) {
> +        pl330_fault(ch, PL330_FAULT_CH_PERIPH_ERR);
> +        return;
> +    }
> +    pl330_dmald(ch, opcode, args, len);
> +}
> +
> +static void pl330_dmalp(PL330Chan *ch, uint8_t opcode, uint8_t *args, int 
> len)
> +{
> +    uint8_t lc = (opcode & 2) >> 1;
> +
> +    ch->lc[lc] = args[0];
> +}
> +
> +static void pl330_dmakill(PL330Chan *ch, uint8_t opcode, uint8_t *args, int 
> len)
> +{
> +    if (ch->state == pl330_chan_fault ||
> +        ch->state == pl330_chan_fault_completing) {
> +        /* This is the only way for a channel to leave the faulting state */
> +        ch->fault_type = 0;
> +        ch->parent->num_faulting--;
> +        if (ch->parent->num_faulting == 0) {
> +            DB_PRINT("abort interrupt lowered\n");
> +            qemu_irq_lower(ch->parent->irq_abort);
> +        }
> +    }
> +    ch->state = pl330_chan_killing;
> +    pl330_fifo_tagged_remove(&ch->parent->fifo, ch->tag);
> +    pl330_queue_remove_tagged(&ch->parent->read_queue, ch->tag);
> +    pl330_queue_remove_tagged(&ch->parent->write_queue, ch->tag);
> +    ch->state = pl330_chan_stopped;
> +}
> +
> +static void pl330_dmalpend(PL330Chan *ch, uint8_t opcode,
> +                                    uint8_t *args, int len)
> +{
> +    uint8_t nf = (opcode & 0x10) >> 4;
> +    uint8_t bs = opcode & 3;
> +    uint8_t lc = (opcode & 4) >> 2;
> +
> +    if (bs == 2) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    if ((bs == 1 && ch->request_flag == PL330_BURST) ||
> +        (bs == 3 && ch->request_flag == PL330_SINGLE)) {
> +        /* Perform NOP */
> +        return;
> +    }
> +    if (!nf || ch->lc[lc]) {
> +        if (nf) {
> +            ch->lc[lc]--;
> +        }
> +        DB_PRINT("loop reiteration\n");
> +        ch->pc -= args[0];
> +        ch->pc -= len + 1;
> +        /* "ch->pc -= args[0] + len + 1" is incorrect when args[0] == 256 */
> +    } else {
> +        DB_PRINT("loop fallthrough\n");
> +    }
> +}
> +
> +
> +static void pl330_dmamov(PL330Chan *ch, uint8_t opcode, uint8_t *args, int 
> len)
> +{
> +    uint8_t rd = args[0] & 7;
> +    uint32_t im;
> +
> +    if ((args[0] >> 3)) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    im = (((uint32_t)args[4]) << 24) | (((uint32_t)args[3]) << 16) |
> +         (((uint32_t)args[2]) << 8)  | (((uint32_t)args[1]));
> +    switch (rd) {
> +    case 0:
> +        ch->src = im;
> +        break;
> +    case 1:
> +        ch->control = im;
> +        break;
> +    case 2:
> +        ch->dst = im;
> +        break;
> +    default:
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +}
> +
> +static void pl330_dmanop(PL330Chan *ch, uint8_t opcode,
> +                         uint8_t *args, int len)
> +{
> +    /* NOP is NOP. */
> +}
> +
> +static void pl330_dmarmb(PL330Chan *ch, uint8_t opcode, uint8_t *args, int 
> len)
> +{
> +   if (pl330_queue_find_insn(&ch->parent->read_queue, ch->tag, false)) {
> +        ch->state = pl330_chan_at_barrier;
> +        ch->stall = 1;
> +        return;
> +    } else {
> +        ch->state = pl330_chan_executing;
> +    }
> +}
> +
> +static void pl330_dmasev(PL330Chan *ch, uint8_t opcode, uint8_t *args, int 
> len)
> +{
> +    uint8_t ev_id;
> +
> +    if (args[0] & 7) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    ev_id = (args[0] >> 3) & 0x1f;
> +    if (ev_id >= ch->parent->num_events) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    if (ch->ns && !(ch->parent->cfg[CFG_INS] & (1 << ev_id))) {
> +        pl330_fault(ch, PL330_FAULT_EVENT_ERR);
> +        return;
> +    }
> +    if (ch->parent->inten & (1 << ev_id)) {
> +        ch->parent->int_status |= (1 << ev_id);
> +        DB_PRINT("event interrupt raised %d\n", ev_id);
> +        qemu_irq_raise(ch->parent->irq[ev_id]);
> +    } else {
> +        ch->parent->ev_status |= (1 << ev_id);
> +    }
> +}
> +
> +static void pl330_dmast(PL330Chan *ch, uint8_t opcode, uint8_t *args, int 
> len)
> +{
> +    uint8_t bs = opcode & 3;
> +    uint32_t size, num;
> +    bool inc;
> +
> +    if (bs == 2) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    if ((bs == 1 && ch->request_flag == PL330_BURST) ||
> +        (bs == 3 && ch->request_flag == PL330_SINGLE)) {
> +        /* Perform NOP */
> +        return;
> +    }
> +    num = ((ch->control >> 18) & 0xf) + 1;
> +    size = (uint32_t)1 << ((ch->control >> 15) & 0x7);
> +    inc = !!((ch->control >> 14) & 1);
> +    ch->stall = pl330_queue_put_insn(&ch->parent->write_queue, ch->dst,
> +                                    size, num, inc, 0, ch->tag, ch);
> +    if (!ch->stall) {
> +        DB_PRINT("channel:%d address:%08x size:%d num:%d %c\n",
> +                 ch->tag, ch->dst, size, num, inc ? 'Y' : 'N');
> +        ch->dst += inc ? size * num - (ch->dst & (size - 1)) : 0;
> +    }
> +}
> +
> +static void pl330_dmastp(PL330Chan *ch, uint8_t opcode,
> +                         uint8_t *args, int len)
> +{
> +    uint8_t periph_id;
> +
> +    if (args[0] & 7) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    periph_id = (args[0] >> 3) & 0x1f;
> +    if (periph_id >= ch->parent->num_periph_req) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    if (ch->ns && !(ch->parent->cfg[CFG_PNS] & (1 << periph_id))) {
> +        pl330_fault(ch, PL330_FAULT_CH_PERIPH_ERR);
> +        return;
> +    }
> +    pl330_dmast(ch, opcode, args, len);
> +}
> +
> +static void pl330_dmastz(PL330Chan *ch, uint8_t opcode,
> +                         uint8_t *args, int len)
> +{
> +    uint32_t size, num;
> +    bool inc;
> +
> +    num = ((ch->control >> 18) & 0xf) + 1;
> +    size = (uint32_t)1 << ((ch->control >> 15) & 0x7);
> +    inc = !!((ch->control >> 14) & 1);
> +    ch->stall = pl330_queue_put_insn(&ch->parent->write_queue, ch->dst,
> +                                    size, num, inc, 1, ch->tag, ch);
> +    if (inc) {
> +        ch->dst += size * num;
> +    }
> +}
> +
> +static void pl330_dmawfe(PL330Chan *ch, uint8_t opcode,
> +                         uint8_t *args, int len)
> +{
> +    uint8_t ev_id;
> +    int i;
> +
> +    if (args[0] & 5) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    ev_id = (args[0] >> 3) & 0x1f;
> +    if (ev_id >= ch->parent->num_events) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    if (ch->ns && !(ch->parent->cfg[CFG_INS] & (1 << ev_id))) {
> +        pl330_fault(ch, PL330_FAULT_EVENT_ERR);
> +        return;
> +    }
> +    ch->wakeup = ev_id;
> +    ch->state = pl330_chan_waiting_event;
> +    if (~ch->parent->inten & ch->parent->ev_status & 1 << ev_id) {
> +        ch->state = pl330_chan_executing;
> +        /* If anyone else is currently waiting on the same event, let them
> +         * clear the ev_status so they pick up event as well
> +         */
> +        for (i = 0; i < ch->parent->num_chnls; ++i) {
> +            PL330Chan *peer = &ch->parent->chan[i];
> +            if (peer->state == pl330_chan_waiting_event &&
> +                    peer->wakeup == ev_id) {
> +                return;
> +            }
> +        }
> +        ch->parent->ev_status &= ~(1 << ev_id);
> +    } else {
> +        ch->stall = 1;
> +    }
> +}
> +
> +static void pl330_dmawfp(PL330Chan *ch, uint8_t opcode,
> +                         uint8_t *args, int len)
> +{
> +    uint8_t bs = opcode & 3;
> +    uint8_t periph_id;
> +
> +    if (args[0] & 7) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    periph_id = (args[0] >> 3) & 0x1f;
> +    if (periph_id >= ch->parent->num_periph_req) {
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +    if (ch->ns && !(ch->parent->cfg[CFG_PNS] & (1 << periph_id))) {
> +        pl330_fault(ch, PL330_FAULT_CH_PERIPH_ERR);
> +        return;
> +    }
> +    switch (bs) {
> +    case 0: /* S */
> +        ch->request_flag = PL330_SINGLE;
> +        ch->wfp_sbp = 0;
> +        break;
> +    case 1: /* P */
> +        ch->request_flag = PL330_BURST;
> +        ch->wfp_sbp = 2;
> +        break;
> +    case 2: /* B */
> +        ch->request_flag = PL330_BURST;
> +        ch->wfp_sbp = 1;
> +        break;
> +    default:
> +        pl330_fault(ch, PL330_FAULT_OPERAND_INVALID);
> +        return;
> +    }
> +
> +    if (ch->parent->periph_busy[periph_id]) {
> +        ch->state = pl330_chan_waiting_periph;
> +        ch->stall = 1;
> +    } else if (ch->state == pl330_chan_waiting_periph) {
> +        ch->state = pl330_chan_executing;
> +    }
> +}
> +
> +static void pl330_dmawmb(PL330Chan *ch, uint8_t opcode,
> +                         uint8_t *args, int len)
> +{
> +    if (pl330_queue_find_insn(&ch->parent->write_queue, ch->tag, false)) {
> +        ch->state = pl330_chan_at_barrier;
> +        ch->stall = 1;
> +        return;
> +    } else {
> +        ch->state = pl330_chan_executing;
> +    }
> +}
> +
> +/* NULL terminated array of the instruction descriptions. */
> +static const PL330InsnDesc insn_desc[] = {
> +    { .opcode = 0x54, .opmask = 0xFD, .size = 3, .exec = pl330_dmaaddh, },
> +    { .opcode = 0x00, .opmask = 0xFF, .size = 1, .exec = pl330_dmaend, },
> +    { .opcode = 0x35, .opmask = 0xFF, .size = 2, .exec = pl330_dmaflushp, },
> +    { .opcode = 0xA0, .opmask = 0xFD, .size = 6, .exec = pl330_dmago, },
> +    { .opcode = 0x04, .opmask = 0xFC, .size = 1, .exec = pl330_dmald, },
> +    { .opcode = 0x25, .opmask = 0xFD, .size = 2, .exec = pl330_dmaldp, },
> +    { .opcode = 0x20, .opmask = 0xFD, .size = 2, .exec = pl330_dmalp, },
> +    /* dmastp  must be before dmalpend in this list, because their maps
> +     * are overlapping
> +     */
> +    { .opcode = 0x29, .opmask = 0xFD, .size = 2, .exec = pl330_dmastp, },
> +    { .opcode = 0x28, .opmask = 0xE8, .size = 2, .exec = pl330_dmalpend, },
> +    { .opcode = 0x01, .opmask = 0xFF, .size = 1, .exec = pl330_dmakill, },
> +    { .opcode = 0xBC, .opmask = 0xFF, .size = 6, .exec = pl330_dmamov, },
> +    { .opcode = 0x18, .opmask = 0xFF, .size = 1, .exec = pl330_dmanop, },
> +    { .opcode = 0x12, .opmask = 0xFF, .size = 1, .exec = pl330_dmarmb, },
> +    { .opcode = 0x34, .opmask = 0xFF, .size = 2, .exec = pl330_dmasev, },
> +    { .opcode = 0x08, .opmask = 0xFC, .size = 1, .exec = pl330_dmast, },
> +    { .opcode = 0x0C, .opmask = 0xFF, .size = 1, .exec = pl330_dmastz, },
> +    { .opcode = 0x36, .opmask = 0xFF, .size = 2, .exec = pl330_dmawfe, },
> +    { .opcode = 0x30, .opmask = 0xFC, .size = 2, .exec = pl330_dmawfp, },
> +    { .opcode = 0x13, .opmask = 0xFF, .size = 1, .exec = pl330_dmawmb, },
> +    { .opcode = 0x00, .opmask = 0x00, .size = 0, .exec = NULL, }
> +};
> +
> +/* Instructions which can be issued via debug registers. */
> +static const PL330InsnDesc debug_insn_desc[] = {
> +    { .opcode = 0xA0, .opmask = 0xFD, .size = 6, .exec = pl330_dmago, },
> +    { .opcode = 0x01, .opmask = 0xFF, .size = 1, .exec = pl330_dmakill, },
> +    { .opcode = 0x34, .opmask = 0xFF, .size = 2, .exec = pl330_dmasev, },
> +    { .opcode = 0x00, .opmask = 0x00, .size = 0, .exec = NULL, }
> +};
> +
> +static inline const PL330InsnDesc *pl330_fetch_insn(PL330Chan *ch)
> +{
> +    uint8_t opcode;
> +    int i;
> +
> +    dma_memory_read(&dma_context_memory, ch->pc, &opcode, 1);
> +    for (i = 0; insn_desc[i].size; i++) {
> +        if ((opcode & insn_desc[i].opmask) == insn_desc[i].opcode) {
> +            return &insn_desc[i];
> +        }
> +    }
> +    return NULL;
> +}
> +
> +static inline void pl330_exec_insn(PL330Chan *ch, const PL330InsnDesc *insn)
> +{
> +    uint8_t buf[PL330_INSN_MAXSIZE];
> +
> +    assert(insn->size <= PL330_INSN_MAXSIZE);
> +    dma_memory_read(&dma_context_memory, ch->pc, buf, insn->size);
> +    insn->exec(ch, buf[0], &buf[1], insn->size - 1);
> +}
> +
> +static inline void pl330_update_pc(PL330Chan *ch,
> +                                   const PL330InsnDesc *insn)
> +{
> +    ch->pc += insn->size;
> +}
> +
> +/* Try to execute current instruction in channel CH. Number of executed
> +   instructions is returned (0 or 1). */
> +static int pl330_chan_exec(PL330Chan *ch)
> +{
> +    const PL330InsnDesc *insn;
> +
> +    if (ch->state != pl330_chan_executing &&
> +            ch->state != pl330_chan_waiting_periph &&
> +            ch->state != pl330_chan_at_barrier &&
> +            ch->state != pl330_chan_waiting_event) {
> +        DB_PRINT("%d\n", ch->state);
> +        return 0;
> +    }
> +    ch->stall = 0;
> +    insn = pl330_fetch_insn(ch);
> +    if (!insn) {
> +        DB_PRINT("pl330 undefined instruction\n");
> +        pl330_fault(ch, PL330_FAULT_UNDEF_INSTR);
> +        return 0;
> +    }
> +    pl330_exec_insn(ch, insn);
> +    if (!ch->stall) {
> +        pl330_update_pc(ch, insn);
> +        ch->watchdog_timer = 0;
> +        return 1;
> +    /* WDT only active in exec state */
> +    } else if (ch->state == pl330_chan_executing) {
> +        ch->watchdog_timer++;
> +        if (ch->watchdog_timer >= PL330_WATCHDOG_LIMIT) {
> +            pl330_fault(ch, PL330_FAULT_LOCKUP_ERR);
> +        }
> +    }
> +    return 0;
> +}
> +
> +/* Try to execute 1 instruction in each channel, one instruction from read
> +   queue and one instruction from write queue. Number of successfully 
> executed
> +   instructions is returned. */
> +static int pl330_exec_cycle(PL330Chan *channel)
> +{
> +    PL330 *s = channel->parent;
> +    PL330QueueEntry *q;
> +    int i;
> +    int num_exec = 0;
> +    int fifo_res = 0;
> +    uint8_t buf[PL330_MAX_BURST_LEN];
> +
> +    /* Execute one instruction in each channel */
> +    num_exec += pl330_chan_exec(channel);
> +
> +    /* Execute one instruction from read queue */
> +    q = pl330_queue_find_insn(&s->read_queue, PL330_UNTAGGED, true);
> +    if (q != NULL && q->len <= pl330_fifo_num_free(&s->fifo)) {
> +        int len = q->len - (q->addr & (q->len - 1));
> +
> +        dma_memory_read(&dma_context_memory, q->addr, buf, len);
> +        if (PL330_ERR_DEBUG > 1) {
> +            DB_PRINT("PL330 read from memory @%08x (size = %08x):\n",
> +                      q->addr, len);
> +            hexdump((char *)buf, stderr, "", len);
> +        }
> +        fifo_res = pl330_fifo_push(&s->fifo, buf, len, q->tag);
> +        if (fifo_res == PL330_FIFO_OK) {
> +            if (q->inc) {
> +                q->addr += len;
> +            }
> +            q->n--;
> +            if (!q->n) {
> +                pl330_queue_remove_insn(&s->read_queue, q);
> +            }
> +            num_exec++;
> +        }
> +    }
> +
> +    /* Execute one instruction from write queue. */
> +    q = pl330_queue_find_insn(&s->write_queue, pl330_fifo_tag(&s->fifo), 
> true);
> +    if (q != NULL) {
> +        int len = q->len - (q->addr & (q->len - 1));
> +
> +        if (q->z) {
> +            for (i = 0; i < len; i++) {
> +                buf[i] = 0;
> +            }
> +        } else {
> +            fifo_res = pl330_fifo_get(&s->fifo, buf, len, q->tag);
> +        }
> +        if (fifo_res == PL330_FIFO_OK || q->z) {
> +            dma_memory_write(&dma_context_memory, q->addr, buf, len);
> +            if (PL330_ERR_DEBUG > 1) {
> +                DB_PRINT("PL330 read from memory @%08x (size = %08x):\n",
> +                         q->addr, len);
> +                hexdump((char *)buf, stderr, "", len);
> +            }
> +            if (q->inc) {
> +                q->addr += len;
> +            }
> +            num_exec++;
> +        } else if (fifo_res == PL330_FIFO_STALL) {
> +            pl330_fault(&channel->parent->chan[q->tag],
> +                                PL330_FAULT_FIFOEMPTY_ERR);
> +        }
> +        q->n--;
> +        if (!q->n) {
> +            pl330_queue_remove_insn(&s->write_queue, q);
> +        }
> +    }
> +
> +    return num_exec;
> +}
> +
> +static int pl330_exec_channel(PL330Chan *channel)
> +{
> +    int insr_exec = 0;
> +
> +    /* TODO: Is it all right to execute everything or should we do per-cycle
> +       simulation? */
> +    while (pl330_exec_cycle(channel)) {
> +        insr_exec++;
> +    }
> +
> +    /* Detect deadlock */
> +    if (channel->state == pl330_chan_executing) {
> +        pl330_fault(channel, PL330_FAULT_LOCKUP_ERR);
> +    }
> +    /* Situation when one of the queues has deadlocked but all channels
> +     * have finished their programs should be impossible.
> +     */
> +
> +    return insr_exec;
> +}
> +
> +static inline void pl330_exec(PL330 *s)
> +{
> +    DB_PRINT("\n");
> +    int i, insr_exec;
> +    do {
> +        insr_exec = pl330_exec_channel(&s->manager);
> +
> +        for (i = 0; i < s->num_chnls; i++) {
> +            insr_exec += pl330_exec_channel(&s->chan[i]);
> +        }
> +    } while (insr_exec);
> +}
> +
> +static void pl330_exec_cycle_timer(void *opaque)
> +{
> +    PL330 *s = (PL330 *)opaque;
> +    pl330_exec(s);
> +}
> +
> +/* Stop or restore dma operations */
> +
> +static void pl330_dma_stop_irq(void *opaque, int irq, int level)
> +{
> +    PL330 *s = (PL330 *)opaque;
> +
> +    if (s->periph_busy[irq] != level) {
> +        s->periph_busy[irq] = level;
> +        qemu_mod_timer(s->timer, qemu_get_clock_ns(vm_clock));
> +    }
> +}
> +
> +static void pl330_debug_exec(PL330 *s)
> +{
> +    uint8_t args[5];
> +    uint8_t opcode;
> +    uint8_t chan_id;
> +    int i;
> +    PL330Chan *ch;
> +    const PL330InsnDesc *insn;
> +
> +    s->debug_status = 1;
> +    chan_id = (s->dbg[0] >>  8) & 0x07;
> +    opcode  = (s->dbg[0] >> 16) & 0xff;
> +    args[0] = (s->dbg[0] >> 24) & 0xff;
> +    args[1] = (s->dbg[1] >>  0) & 0xff;
> +    args[2] = (s->dbg[1] >>  8) & 0xff;
> +    args[3] = (s->dbg[1] >> 16) & 0xff;
> +    args[4] = (s->dbg[1] >> 24) & 0xff;
> +    DB_PRINT("chan id: %d\n", chan_id);
> +    if (s->dbg[0] & 1) {
> +        ch = &s->chan[chan_id];
> +    } else {
> +        ch = &s->manager;
> +    }
> +    insn = NULL;
> +    for (i = 0; debug_insn_desc[i].size; i++) {
> +        if ((opcode & debug_insn_desc[i].opmask) == 
> debug_insn_desc[i].opcode) {
> +            insn = &debug_insn_desc[i];
> +        }
> +    }
> +    if (!insn) {
> +        pl330_fault(ch, PL330_FAULT_UNDEF_INSTR | PL330_FAULT_DBG_INSTR);
> +        return ;
> +    }
> +    ch->stall = 0;
> +    insn->exec(ch, opcode, args, insn->size - 1);
> +    if (ch->fault_type) {
> +        ch->fault_type |= PL330_FAULT_DBG_INSTR;
> +    }
> +    if (ch->stall) {
> +        qemu_log_mask(LOG_UNIMP, "pl330: stall of debug instruction not "
> +                      "implemented\n");
> +    }
> +    s->debug_status = 0;
> +}
> +
> +/* IOMEM mapped registers */
> +
> +static void pl330_iomem_write(void *opaque, hwaddr offset,
> +                              uint64_t value, unsigned size)
> +{
> +    PL330 *s = (PL330 *) opaque;
> +    uint32_t i;
> +
> +    DB_PRINT("addr: %08x data: %08x\n", (unsigned)offset, (unsigned)value);
> +
> +    switch (offset) {
> +    case PL330_REG_INTEN:
> +        s->inten = value;
> +        break;
> +    case PL330_REG_INTCLR:
> +        for (i = 0; i < s->num_events; i++) {
> +            if (s->int_status & s->inten & value & (1 << i)) {
> +                DB_PRINT("event interrupt lowered %d\n", i);
> +                qemu_irq_lower(s->irq[i]);
> +            }
> +        }
> +        s->ev_status &= ~(value & s->inten);
> +        s->int_status &= ~(value & s->inten);
> +        break;
> +    case PL330_REG_DBGCMD:
> +        if ((value & 3) == 0) {
> +            pl330_debug_exec(s);
> +            pl330_exec(s);
> +        } else {
> +            qemu_log_mask(LOG_GUEST_ERROR, "pl330: write of illegal value %u 
> "
> +                          "for offset " TARGET_FMT_plx "\n", (unsigned)value,
> +                          offset);
> +        }
> +        break;
> +    case PL330_REG_DBGINST0:
> +        DB_PRINT("s->dbg[0] = %08x\n", (unsigned)value);
> +        s->dbg[0] = value;
> +        break;
> +    case PL330_REG_DBGINST1:
> +        DB_PRINT("s->dbg[1] = %08x\n", (unsigned)value);
> +        s->dbg[1] = value;
> +        break;
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR, "pl330: bad write offset " 
> TARGET_FMT_plx
> +                      "\n", offset);
> +        break;
> +    }
> +}
> +
> +static inline uint32_t pl330_iomem_read_imp(void *opaque,
> +        hwaddr offset)
> +{
> +    PL330 *s = (PL330 *)opaque;
> +    int chan_id;
> +    int i;
> +    uint32_t res;
> +
> +    if (offset >= PL330_REG_PERIPH_ID && offset < PL330_REG_PERIPH_ID + 32) {
> +        return pl330_id[(offset - PL330_REG_PERIPH_ID) >> 2];
> +    }
> +    if (offset >= PL330_REG_CR0_BASE && offset < PL330_REG_CR0_BASE + 24) {
> +        return s->cfg[(offset - PL330_REG_CR0_BASE) >> 2];
> +    }
> +    if (offset >= PL330_REG_CHANCTRL && offset < PL330_REG_DBGSTATUS) {
> +        offset -= PL330_REG_CHANCTRL;
> +        chan_id = offset >> 5;
> +        if (chan_id >= s->num_chnls) {
> +            qemu_log_mask(LOG_GUEST_ERROR, "pl330: bad read offset "
> +                          TARGET_FMT_plx "\n", offset);
> +        }
> +        switch (offset & 0x1f) {
> +        case 0x00:
> +            return s->chan[chan_id].src;
> +        case 0x04:
> +            return s->chan[chan_id].dst;
> +        case 0x08:
> +            return s->chan[chan_id].control;
> +        case 0x0C:
> +            return s->chan[chan_id].lc[0];
> +        case 0x10:
> +            return s->chan[chan_id].lc[1];
> +        default:
> +            qemu_log_mask(LOG_GUEST_ERROR, "pl330: bad read offset "
> +                          TARGET_FMT_plx "\n", offset);
> +        }
> +    }
> +    if (offset >= PL330_REG_CSR_BASE && offset < 0x400) {
> +        offset -= PL330_REG_CSR_BASE;
> +        chan_id = offset >> 3;
> +        if (chan_id >= s->num_chnls) {
> +            qemu_log_mask(LOG_GUEST_ERROR, "pl330: bad read offset "
> +                          TARGET_FMT_plx "\n", offset);
> +        }
> +        switch ((offset >> 2) & 1) {
> +        case 0x0:
> +            res = (s->chan[chan_id].ns << 21) |
> +                    (s->chan[chan_id].wakeup << 4) |
> +                    (s->chan[chan_id].state) |
> +                    (s->chan[chan_id].wfp_sbp << 14);
> +            return res;
> +        case 0x1:
> +            return s->chan[chan_id].pc;
> +        default:
> +            qemu_log_mask(LOG_GUEST_ERROR, "pl330: read error\n");
> +        }
> +    }
> +    if (offset >= PL330_REG_FTR_BASE && offset < 0x100) {
> +        offset -= PL330_REG_FTR_BASE;
> +        chan_id = offset >> 2;
> +        if (chan_id >= s->num_chnls) {
> +            qemu_log_mask(LOG_GUEST_ERROR, "pl330: bad read offset "
> +                          TARGET_FMT_plx "\n", offset);
> +        }
> +        return s->chan[chan_id].fault_type;
> +    }
> +    switch (offset) {
> +    case PL330_REG_DSR:
> +        return (s->manager.ns << 9) | (s->manager.wakeup << 4) |
> +            (s->manager.state & 0xf);
> +    case PL330_REG_DPC:
> +        return s->manager.pc;
> +    case PL330_REG_INTEN:
> +        return s->inten;
> +    case PL330_REG_INT_EVENT_RIS:
> +        return s->ev_status;
> +    case PL330_REG_INTMIS:
> +        return s->int_status;
> +    case PL330_REG_INTCLR:
> +        /* Documentation says that we can't read this register
> +         * but linux kernel does it
> +         */
> +        return 0;
> +    case PL330_REG_FSRD:
> +        return s->manager.state ? 1 : 0;
> +    case PL330_REG_FSRC:
> +        res = 0;
> +        for (i = 0; i < s->num_chnls; i++) {
> +            if (s->chan[i].state == pl330_chan_fault ||
> +                s->chan[i].state == pl330_chan_fault_completing) {
> +                res |= 1 << i;
> +            }
> +        }
> +        return res;
> +    case PL330_REG_FTRD:
> +        return s->manager.fault_type;
> +    case PL330_REG_DBGSTATUS:
> +        return s->debug_status;
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR, "pl330: bad read offset "
> +                      TARGET_FMT_plx "\n", offset);
> +    }
> +    return 0;
> +}
> +
> +static uint64_t pl330_iomem_read(void *opaque, hwaddr offset,
> +        unsigned size)
> +{
> +    int ret = pl330_iomem_read_imp(opaque, offset);
> +    DB_PRINT("addr: %08x data: %08x\n", (unsigned)offset, ret);
> +    return ret;
> +}
> +
> +static const MemoryRegionOps pl330_ops = {
> +    .read = pl330_iomem_read,
> +    .write = pl330_iomem_write,
> +    .endianness = DEVICE_LITTLE_ENDIAN,
> +    .impl = {
> +        .min_access_size = 4,
> +        .max_access_size = 4,
> +    }
> +};
> +
> +/* Controller logic and initialization */
> +
> +static void pl330_chan_reset(PL330Chan *ch)
> +{
> +    ch->src = 0;
> +    ch->dst = 0;
> +    ch->pc = 0;
> +    ch->state = pl330_chan_stopped;
> +    ch->watchdog_timer = 0;
> +    ch->stall = 0;
> +    ch->control = 0;
> +    ch->status = 0;
> +    ch->fault_type = 0;
> +}
> +
> +static void pl330_reset(DeviceState *d)
> +{
> +    int i;
> +    PL330 *s = FROM_SYSBUS(PL330, SYS_BUS_DEVICE(d));
> +
> +    s->inten = 0;
> +    s->int_status = 0;
> +    s->ev_status = 0;
> +    s->debug_status = 0;
> +    s->num_faulting = 0;
> +    s->manager.ns = s->mgr_ns_at_rst;
> +    pl330_fifo_reset(&s->fifo);
> +    pl330_queue_reset(&s->read_queue);
> +    pl330_queue_reset(&s->write_queue);
> +
> +    for (i = 0; i < s->num_chnls; i++) {
> +        pl330_chan_reset(&s->chan[i]);
> +    }
> +    for (i = 0; i < s->num_periph_req; i++) {
> +        s->periph_busy[i] = 0;
> +    }
> +
> +    qemu_del_timer(s->timer);
> +}
> +
> +static int pl330_init(SysBusDevice *dev)
> +{
> +    int i;
> +    PL330 *s = FROM_SYSBUS(PL330, dev);
> +
> +    sysbus_init_irq(dev, &s->irq_abort);
> +    memory_region_init_io(&s->iomem, &pl330_ops, s, "dma", PL330_IOMEM_SIZE);
> +    sysbus_init_mmio(dev, &s->iomem);
> +
> +    s->timer = qemu_new_timer_ns(vm_clock, pl330_exec_cycle_timer, s);
> +
> +    s->cfg[0] = (s->mgr_ns_at_rst ? 0x4 : 0) |
> +                (s->num_periph_req > 0 ? 1 : 0) |
> +                ((s->num_chnls - 1) & 0x7) << 4 |
> +                ((s->num_periph_req - 1) & 0x1f) << 12 |
> +                ((s->num_events - 1) & 0x1f) << 17;
> +
> +    switch (s->i_cache_len) {
> +    case (4):
> +        s->cfg[1] |= 2;
> +        break;
> +    case (8):
> +        s->cfg[1] |= 3;
> +        break;
> +    case (16):
> +        s->cfg[1] |= 4;
> +        break;
> +    case (32):
> +        s->cfg[1] |= 5;
> +        break;
> +    default:
> +        hw_error("Bad value for i-cache_len property: %d\n", s->i_cache_len);
> +    }
> +    s->cfg[1] |= ((s->num_i_cache_lines - 1) & 0xf) << 4;
> +
> +    s->chan = g_new0(PL330Chan, s->num_chnls);
> +    s->hi_seqn = g_new0(uint8_t, s->num_chnls);
> +    s->lo_seqn = g_new0(uint8_t, s->num_chnls);
> +    for (i = 0; i < s->num_chnls; i++) {
> +        s->chan[i].parent = s;
> +        s->chan[i].tag = (uint8_t)i;
> +    }
> +    s->manager.parent = s;
> +    s->manager.tag = s->num_chnls;
> +    s->manager.is_manager = true;
> +
> +    s->irq = g_new0(qemu_irq, s->num_events);
> +    for (i = 0; i < s->num_events; i++) {
> +        sysbus_init_irq(dev, &s->irq[i]);
> +    }
> +
> +    qdev_init_gpio_in(&dev->qdev, pl330_dma_stop_irq, PL330_PERIPH_NUM);
> +
> +    switch (s->data_width) {
> +    case (32):
> +        s->cfg[CFG_CRD] |= 0x2;
> +        break;
> +    case (64):
> +        s->cfg[CFG_CRD] |= 0x3;
> +        break;
> +    case (128):
> +        s->cfg[CFG_CRD] |= 0x4;
> +        break;
> +    default:
> +        hw_error("Bad value for data_width property: %d\n", s->data_width);
> +    }
> +
> +    s->cfg[CFG_CRD] |= ((s->wr_cap - 1) & 0x7) << 4 |
> +                    ((s->wr_q_dep - 1) & 0xf) << 8 |
> +                    ((s->rd_cap - 1) & 0x7) << 12 |
> +                    ((s->rd_q_dep - 1) & 0xf) << 16 |
> +                    ((s->data_buffer_dep - 1) & 0x1ff) << 20;
> +
> +    pl330_queue_init(&s->read_queue, s->rd_q_dep, s->num_chnls, s);
> +    pl330_queue_init(&s->write_queue, s->wr_q_dep, s->num_chnls, s);
> +    pl330_fifo_init(&s->fifo, s->data_buffer_dep);
> +
> +    return 0;
> +}
> +
> +static Property pl330_properties[] = {
> +    /* CR0 */
> +    DEFINE_PROP_UINT32("num_chnls", PL330, num_chnls, 8),
> +    DEFINE_PROP_UINT8("num_periph_req", PL330, num_periph_req, 4),
> +    DEFINE_PROP_UINT8("num_events", PL330, num_events, 16),
> +    DEFINE_PROP_UINT8("mgr_ns_at_rst", PL330, mgr_ns_at_rst, 0),
> +    /* CR1 */
> +    DEFINE_PROP_UINT8("i-cache_len", PL330, i_cache_len, 4),
> +    DEFINE_PROP_UINT8("num_i-cache_lines", PL330, num_i_cache_lines, 8),
> +    /* CR2-4 */
> +    DEFINE_PROP_UINT32("boot_addr", PL330, cfg[CFG_BOOT_ADDR], 0),
> +    DEFINE_PROP_UINT32("INS", PL330, cfg[CFG_INS], 0),
> +    DEFINE_PROP_UINT32("PNS", PL330, cfg[CFG_PNS], 0),
> +    /* CRD */
> +    DEFINE_PROP_UINT8("data_width", PL330, data_width, 64),
> +    DEFINE_PROP_UINT8("wr_cap", PL330, wr_cap, 8),
> +    DEFINE_PROP_UINT8("wr_q_dep", PL330, wr_q_dep, 16),
> +    DEFINE_PROP_UINT8("rd_cap", PL330, rd_cap, 8),
> +    DEFINE_PROP_UINT8("rd_q_dep", PL330, rd_q_dep, 16),
> +    DEFINE_PROP_UINT16("data_buffer_dep", PL330, data_buffer_dep, 256),
> +
> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
> +static void pl330_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
> +
> +    k->init = pl330_init;
> +    dc->reset = pl330_reset;
> +    dc->props = pl330_properties;
> +    dc->vmsd = &vmstate_pl330;
> +}
> +
> +static const TypeInfo pl330_type_info = {
> +    .name           = "pl330",
> +    .parent         = TYPE_SYS_BUS_DEVICE,
> +    .instance_size  = sizeof(PL330),
> +    .class_init      = pl330_class_init,
> +};
> +
> +static void pl330_register_types(void)
> +{
> +    type_register_static(&pl330_type_info);
> +}
> +
> +type_init(pl330_register_types)
> --
> 1.7.0.4
>
>
>



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