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Re: [Qemu-devel] [PATCH v2] ppc4xx_i2c: Implement basic I2C functions
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From: |
David Gibson |
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Subject: |
Re: [Qemu-devel] [PATCH v2] ppc4xx_i2c: Implement basic I2C functions |
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Date: |
Mon, 18 Dec 2017 15:03:03 +1100 |
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User-agent: |
Mutt/1.9.1 (2017-09-22) |
On Sat, Dec 16, 2017 at 11:42:14PM +0100, BALATON Zoltan wrote:
> Enough to please U-Boot and make it able to detect SDRAM SPD EEPROMs
>
> Signed-off-by: François Revol <address@hidden>
> Signed-off-by: BALATON Zoltan <address@hidden>
> Reviewed-by: David Gibson <address@hidden>
Applied to ppc-for-2.12, thanks.
> ---
> v2:
> - Removed DPRINTFs, no other change
> - R-b from:
> http://lists.nongnu.org/archive/html/qemu-ppc/2017-08/msg00193.html
>
> hw/i2c/ppc4xx_i2c.c | 198
> +++++++++++++++++++++++++++++++++++++-------
> include/hw/i2c/ppc4xx_i2c.h | 3 +
> 2 files changed, 171 insertions(+), 30 deletions(-)
>
> diff --git a/hw/i2c/ppc4xx_i2c.c b/hw/i2c/ppc4xx_i2c.c
> index 5a6bde9..e873a44 100644
> --- a/hw/i2c/ppc4xx_i2c.c
> +++ b/hw/i2c/ppc4xx_i2c.c
> @@ -2,6 +2,8 @@
> * PPC4xx I2C controller emulation
> *
> * Copyright (c) 2007 Jocelyn Mayer
> + * Copyright (c) 2012 François Revol
> + * Copyright (c) 2016 BALATON Zoltan
> *
> * Permission is hereby granted, free of charge, to any person obtaining a
> copy
> * of this software and associated documentation files (the "Software"), to
> deal
> @@ -25,26 +27,118 @@
> #include "qemu/osdep.h"
> #include "qapi/error.h"
> #include "qemu-common.h"
> +#include "qemu/log.h"
> #include "cpu.h"
> #include "hw/hw.h"
> #include "hw/i2c/ppc4xx_i2c.h"
>
> -/*#define DEBUG_I2C*/
> +#define PPC4xx_I2C_MEM_SIZE 0x12
>
> -#define PPC4xx_I2C_MEM_SIZE 0x11
> +#define IIC_CNTL_PT (1 << 0)
> +#define IIC_CNTL_READ (1 << 1)
> +#define IIC_CNTL_CHT (1 << 2)
> +#define IIC_CNTL_RPST (1 << 3)
> +
> +#define IIC_STS_PT (1 << 0)
> +#define IIC_STS_ERR (1 << 2)
> +#define IIC_STS_MDBS (1 << 5)
> +
> +#define IIC_EXTSTS_XFRA (1 << 0)
> +
> +#define IIC_XTCNTLSS_SRST (1 << 0)
> +
> +static void ppc4xx_i2c_reset(DeviceState *s)
> +{
> + PPC4xxI2CState *i2c = PPC4xx_I2C(s);
> +
> + /* FIXME: Should also reset bus?
> + *if (s->address != ADDR_RESET) {
> + * i2c_end_transfer(s->bus);
> + *}
> + */
> +
> + i2c->mdata = 0;
> + i2c->lmadr = 0;
> + i2c->hmadr = 0;
> + i2c->cntl = 0;
> + i2c->mdcntl = 0;
> + i2c->sts = 0;
> + i2c->extsts = 0x8f;
> + i2c->sdata = 0;
> + i2c->lsadr = 0;
> + i2c->hsadr = 0;
> + i2c->clkdiv = 0;
> + i2c->intrmsk = 0;
> + i2c->xfrcnt = 0;
> + i2c->xtcntlss = 0;
> + i2c->directcntl = 0x0f;
> + i2c->intr = 0;
> +}
> +
> +static inline bool ppc4xx_i2c_is_master(PPC4xxI2CState *i2c)
> +{
> + return true;
> +}
>
> static uint64_t ppc4xx_i2c_readb(void *opaque, hwaddr addr, unsigned int
> size)
> {
> PPC4xxI2CState *i2c = PPC4xx_I2C(opaque);
> uint64_t ret;
>
> -#ifdef DEBUG_I2C
> - printf("%s: addr " TARGET_FMT_plx "\n", __func__, addr);
> -#endif
> switch (addr) {
> case 0x00:
> - /*i2c_readbyte(&i2c->mdata);*/
> ret = i2c->mdata;
> + if (ppc4xx_i2c_is_master(i2c)) {
> + ret = 0xff;
> +
> + if (!(i2c->sts & IIC_STS_MDBS)) {
> + qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Trying to read "
> + "without starting transfer\n",
> + TYPE_PPC4xx_I2C, __func__);
> + } else {
> + int pending = (i2c->cntl >> 4) & 3;
> +
> + /* get the next byte */
> + int byte = i2c_recv(i2c->bus);
> +
> + if (byte < 0) {
> + qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: read failed "
> + "for device 0x%02x\n", TYPE_PPC4xx_I2C,
> + __func__, i2c->lmadr);
> + ret = 0xff;
> + } else {
> + ret = byte;
> + /* Raise interrupt if enabled */
> + /*ppc4xx_i2c_raise_interrupt(i2c)*/;
> + }
> +
> + if (!pending) {
> + i2c->sts &= ~IIC_STS_MDBS;
> + /*i2c_end_transfer(i2c->bus);*/
> + /*} else if (i2c->cntl & (IIC_CNTL_RPST | IIC_CNTL_CHT)) {*/
> + } else if (pending) {
> + /* current smbus implementation doesn't like
> + multibyte xfer repeated start */
> + i2c_end_transfer(i2c->bus);
> + if (i2c_start_transfer(i2c->bus, i2c->lmadr >> 1, 1)) {
> + /* if non zero is returned, the adress is not valid
> */
> + i2c->sts &= ~IIC_STS_PT;
> + i2c->sts |= IIC_STS_ERR;
> + i2c->extsts |= IIC_EXTSTS_XFRA;
> + } else {
> + /*i2c->sts |= IIC_STS_PT;*/
> + i2c->sts |= IIC_STS_MDBS;
> + i2c->sts &= ~IIC_STS_ERR;
> + i2c->extsts = 0;
> + }
> + }
> + pending--;
> + i2c->cntl = (i2c->cntl & 0xcf) | (pending << 4);
> + }
> + } else {
> + qemu_log_mask(LOG_UNIMP, "[%s]%s: slave mode not implemented\n",
> + TYPE_PPC4xx_I2C, __func__);
> + }
> break;
> case 0x02:
> ret = i2c->sdata;
> @@ -88,13 +182,15 @@ static uint64_t ppc4xx_i2c_readb(void *opaque, hwaddr
> addr, unsigned int size)
> case 0x10:
> ret = i2c->directcntl;
> break;
> + case 0x11:
> + ret = i2c->intr;
> + break;
> default:
> - ret = 0x00;
> + qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad address at offset 0x%"
> + HWADDR_PRIx "\n", TYPE_PPC4xx_I2C, __func__, addr);
> + ret = 0;
> break;
> }
> -#ifdef DEBUG_I2C
> - printf("%s: addr " TARGET_FMT_plx " %02" PRIx64 "\n", __func__, addr,
> ret);
> -#endif
>
> return ret;
> }
> @@ -103,26 +199,70 @@ static void ppc4xx_i2c_writeb(void *opaque, hwaddr
> addr, uint64_t value,
> unsigned int size)
> {
> PPC4xxI2CState *i2c = opaque;
> -#ifdef DEBUG_I2C
> - printf("%s: addr " TARGET_FMT_plx " val %08" PRIx64 "\n",
> - __func__, addr, value);
> -#endif
> +
> switch (addr) {
> case 0x00:
> i2c->mdata = value;
> - /*i2c_sendbyte(&i2c->mdata);*/
> + if (!i2c_bus_busy(i2c->bus)) {
> + /* assume we start a write transfer */
> + if (i2c_start_transfer(i2c->bus, i2c->lmadr >> 1, 0)) {
> + /* if non zero is returned, the adress is not valid */
> + i2c->sts &= ~IIC_STS_PT;
> + i2c->sts |= IIC_STS_ERR;
> + i2c->extsts |= IIC_EXTSTS_XFRA;
> + } else {
> + i2c->sts |= IIC_STS_PT;
> + i2c->sts &= ~IIC_STS_ERR;
> + i2c->extsts = 0;
> + }
> + }
> + if (i2c_bus_busy(i2c->bus)) {
> + if (i2c_send(i2c->bus, i2c->mdata)) {
> + /* if the target return non zero then end the transfer */
> + i2c->sts &= ~IIC_STS_PT;
> + i2c->sts |= IIC_STS_ERR;
> + i2c->extsts |= IIC_EXTSTS_XFRA;
> + i2c_end_transfer(i2c->bus);
> + }
> + }
> break;
> case 0x02:
> i2c->sdata = value;
> break;
> case 0x04:
> i2c->lmadr = value;
> + if (i2c_bus_busy(i2c->bus)) {
> + i2c_end_transfer(i2c->bus);
> + }
> break;
> case 0x05:
> i2c->hmadr = value;
> break;
> case 0x06:
> i2c->cntl = value;
> + if (i2c->cntl & IIC_CNTL_PT) {
> + if (i2c->cntl & IIC_CNTL_READ) {
> + if (i2c_bus_busy(i2c->bus)) {
> + /* end previous transfer */
> + i2c->sts &= ~IIC_STS_PT;
> + i2c_end_transfer(i2c->bus);
> + }
> + if (i2c_start_transfer(i2c->bus, i2c->lmadr >> 1, 1)) {
> + /* if non zero is returned, the adress is not valid */
> + i2c->sts &= ~IIC_STS_PT;
> + i2c->sts |= IIC_STS_ERR;
> + i2c->extsts |= IIC_EXTSTS_XFRA;
> + } else {
> + /*i2c->sts |= IIC_STS_PT;*/
> + i2c->sts |= IIC_STS_MDBS;
> + i2c->sts &= ~IIC_STS_ERR;
> + i2c->extsts = 0;
> + }
> + } else {
> + /* we actually already did the write transfer... */
> + i2c->sts &= ~IIC_STS_PT;
> + }
> + }
> break;
> case 0x07:
> i2c->mdcntl = value & 0xDF;
> @@ -135,6 +275,7 @@ static void ppc4xx_i2c_writeb(void *opaque, hwaddr addr,
> uint64_t value,
> break;
> case 0x0A:
> i2c->lsadr = value;
> + /*i2c_set_slave_address(i2c->bus, i2c->lsadr);*/
> break;
> case 0x0B:
> i2c->hsadr = value;
> @@ -149,11 +290,23 @@ static void ppc4xx_i2c_writeb(void *opaque, hwaddr
> addr, uint64_t value,
> i2c->xfrcnt = value & 0x77;
> break;
> case 0x0F:
> + if (value & IIC_XTCNTLSS_SRST) {
> + /* Is it actually a full reset? U-Boot sets some regs before */
> + ppc4xx_i2c_reset(DEVICE(i2c));
> + break;
> + }
> i2c->xtcntlss = value;
> break;
> case 0x10:
> i2c->directcntl = value & 0x7;
> break;
> + case 0x11:
> + i2c->intr = value;
> + break;
> + default:
> + qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad address at offset 0x%"
> + HWADDR_PRIx "\n", TYPE_PPC4xx_I2C, __func__, addr);
> + break;
> }
> }
>
> @@ -167,21 +320,6 @@ static const MemoryRegionOps ppc4xx_i2c_ops = {
> .endianness = DEVICE_NATIVE_ENDIAN,
> };
>
> -static void ppc4xx_i2c_reset(DeviceState *s)
> -{
> - PPC4xxI2CState *i2c = PPC4xx_I2C(s);
> -
> - i2c->mdata = 0x00;
> - i2c->sdata = 0x00;
> - i2c->cntl = 0x00;
> - i2c->mdcntl = 0x00;
> - i2c->sts = 0x00;
> - i2c->extsts = 0x00;
> - i2c->clkdiv = 0x00;
> - i2c->xfrcnt = 0x00;
> - i2c->directcntl = 0x0F;
> -}
> -
> static void ppc4xx_i2c_init(Object *o)
> {
> PPC4xxI2CState *s = PPC4xx_I2C(o);
> diff --git a/include/hw/i2c/ppc4xx_i2c.h b/include/hw/i2c/ppc4xx_i2c.h
> index e53042f..71fb392 100644
> --- a/include/hw/i2c/ppc4xx_i2c.h
> +++ b/include/hw/i2c/ppc4xx_i2c.h
> @@ -2,6 +2,8 @@
> * PPC4xx I2C controller emulation
> *
> * Copyright (c) 2007 Jocelyn Mayer
> + * Copyright (c) 2012 François Revol
> + * Copyright (c) 2016 BALATON Zoltan
> *
> * Permission is hereby granted, free of charge, to any person obtaining a
> copy
> * of this software and associated documentation files (the "Software"), to
> deal
> @@ -56,6 +58,7 @@ typedef struct PPC4xxI2CState {
> uint8_t xfrcnt;
> uint8_t xtcntlss;
> uint8_t directcntl;
> + uint8_t intr;
> } PPC4xxI2CState;
>
> #endif /* PPC4XX_I2C_H */
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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