Re: [Qemu-devel] [PATCH v8 07/24] hw/arm/virt-acpi-build: Generation of DSDT table for virt devices

[Igor Mammedov]

On Thu, 21 May 2015 10:28:34 +0800
Shannon Zhao <address@hidden> wrote:

> From: Shannon Zhao <address@hidden>
> 
> DSDT consists of the usual common table header plus a definition
> block in AML encoding which describes all devices in the platform.
> 
> After initializing DSDT with header information the namespace is
> created which is followed by the device encodings. The devices are
> described using the Resource Template for the 32-Bit Fixed Memory
> Range and the Extended Interrupt Descriptors.
> 
> Signed-off-by: Shannon Zhao <address@hidden>
> Signed-off-by: Shannon Zhao <address@hidden>
> ---
>  hw/arm/virt-acpi-build.c | 130 
> +++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 130 insertions(+)
> 
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index b8a5bd8..a1d6045 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -40,6 +40,132 @@
>  #include "hw/hw.h"
>  #include "hw/acpi/aml-build.h"
>  
> +static void acpi_dsdt_add_cpus(Aml *scope, int smp_cpus)
> +{
> +    uint16_t i;
> +
> +    for (i = 0; i < smp_cpus; i++) {
> +        Aml *dev = aml_device("C%03x", i);
> +        aml_append(dev, aml_name_decl("_HID", aml_string("ACPI0007")));
> +        aml_append(dev, aml_name_decl("_UID", aml_int(i)));
> +        Aml *crs = aml_resource_template();
> +        aml_append(dev, aml_name_decl("_CRS", crs));
what is this empty _CRS for?


> +        aml_append(scope, dev);
> +    }
> +}
> +
> +static void acpi_dsdt_add_uart(Aml *scope, const MemMapEntry *uart_memmap,
> +                                           int uart_irq)
> +{
> +    Aml *dev = aml_device("COM0");
> +    aml_append(dev, aml_name_decl("_HID", aml_string("ARMH0011")));
> +    aml_append(dev, aml_name_decl("_UID", aml_int(0)));
> +
> +    Aml *crs = aml_resource_template();
> +    aml_append(crs, aml_memory32_fixed(uart_memmap->base,
> +                                       uart_memmap->size, AML_READ_WRITE));
> +    aml_append(crs,
> +               aml_interrupt(AML_CONSUMER, AML_LEVEL, AML_ACTIVE_HIGH,
> +                             AML_EXCLUSIVE, uart_irq + 32));
what does magic "+ 32" do here?

> +    aml_append(dev, aml_name_decl("_CRS", crs));
> +    aml_append(scope, dev);
> +}
> +
> +static void acpi_dsdt_add_rtc(Aml *scope, const MemMapEntry *rtc_memmap,
> +                                          int rtc_irq)
> +{
> +    Aml *dev = aml_device("RTC0");
> +    aml_append(dev, aml_name_decl("_HID", aml_string("LNRO0013")));
> +    aml_append(dev, aml_name_decl("_UID", aml_int(0)));
> +
> +    Aml *crs = aml_resource_template();
> +    aml_append(crs, aml_memory32_fixed(rtc_memmap->base,
> +                                       rtc_memmap->size, AML_READ_WRITE));
> +    aml_append(crs,
> +               aml_interrupt(AML_CONSUMER, AML_LEVEL, AML_ACTIVE_HIGH,
> +                             AML_EXCLUSIVE, rtc_irq + 32));
ditto?

> +    aml_append(dev, aml_name_decl("_CRS", crs));
> +    aml_append(scope, dev);
> +}
> +
> +static void acpi_dsdt_add_flash(Aml *scope, const MemMapEntry *flash_memmap)
> +{
> +    Aml *dev, *crs;
> +    hwaddr base = flash_memmap->base;
> +    hwaddr size = flash_memmap->size;
> +
> +    dev = aml_device("FLS0");
> +    aml_append(dev, aml_name_decl("_HID", aml_string("LNRO0015")));
> +    aml_append(dev, aml_name_decl("_UID", aml_int(0)));
> +
> +    crs = aml_resource_template();
> +    aml_append(crs, aml_memory32_fixed(base, size, AML_READ_WRITE));
> +    aml_append(dev, aml_name_decl("_CRS", crs));
> +    aml_append(scope, dev);
> +
> +    dev = aml_device("FLS1");
> +    aml_append(dev, aml_name_decl("_HID", aml_string("LNRO0015")));
> +    aml_append(dev, aml_name_decl("_UID", aml_int(1)));
> +    crs = aml_resource_template();
> +    aml_append(crs, aml_memory32_fixed(base + size, size, AML_READ_WRITE));
> +    aml_append(dev, aml_name_decl("_CRS", crs));
> +    aml_append(scope, dev);
> +}
> +
> +static void acpi_dsdt_add_virtio(Aml *scope,
> +                                 const MemMapEntry *virtio_mmio_memmap,
> +                                 int mmio_irq, int num)
> +{
> +    hwaddr base = virtio_mmio_memmap->base;
> +    hwaddr size = virtio_mmio_memmap->size;
> +    int irq = mmio_irq + 32;
again magic offset

> +    int i;
> +
> +    for (i = 0; i < num; i++) {
> +        Aml *dev = aml_device("VR%02u", i);
> +        aml_append(dev, aml_name_decl("_HID", aml_string("LNRO0005")));
> +        aml_append(dev, aml_name_decl("_UID", aml_int(i)));
> +
> +        Aml *crs = aml_resource_template();
> +        aml_append(crs, aml_memory32_fixed(base, size, AML_READ_WRITE));
> +        aml_append(crs,
> +                   aml_interrupt(AML_CONSUMER, AML_LEVEL, AML_ACTIVE_HIGH,
> +                                 AML_EXCLUSIVE, irq + i));
> +        aml_append(dev, aml_name_decl("_CRS", crs));
> +        aml_append(scope, dev);
> +        base += size;
> +    }
> +}
> +
> +/* DSDT */
> +static void
> +build_dsdt(GArray *table_data, GArray *linker, VirtGuestInfo *guest_info)
> +{
> +    Aml *scope, *dsdt;
> +    const MemMapEntry *memmap = guest_info->memmap;
> +    const int *irqmap = guest_info->irqmap;
> +
> +    dsdt = init_aml_allocator();
> +    /* Reserve space for header */
> +    acpi_data_push(dsdt->buf, sizeof(AcpiTableHeader));
> +
> +    scope = aml_scope("\\_SB");
> +    acpi_dsdt_add_cpus(scope, guest_info->smp_cpus);
> +    acpi_dsdt_add_uart(scope, &memmap[VIRT_UART], irqmap[VIRT_UART]);
> +    acpi_dsdt_add_rtc(scope, &memmap[VIRT_RTC], irqmap[VIRT_RTC]);
> +    acpi_dsdt_add_flash(scope, &memmap[VIRT_FLASH]);
> +    acpi_dsdt_add_virtio(scope, &memmap[VIRT_MMIO],
> +                                irqmap[VIRT_MMIO], NUM_VIRTIO_TRANSPORTS);
> +    aml_append(dsdt, scope);
> +
> +    /* copy AML table into ACPI tables blob and patch header there */
> +    g_array_append_vals(table_data, dsdt->buf->data, dsdt->buf->len);
> +    build_header(linker, table_data,
> +        (void *)(table_data->data + table_data->len - dsdt->buf->len),
> +        "DSDT", dsdt->buf->len, 5);
> +    free_aml_allocator();
> +}
> +
>  typedef
>  struct AcpiBuildState {
>      /* Copy of table in RAM (for patching). */
> @@ -55,6 +181,7 @@ static
>  void virt_acpi_build(VirtGuestInfo *guest_info, AcpiBuildTables *tables)
>  {
>      GArray *table_offsets;
> +    GArray *tables_blob = tables->table_data;
>  
>      table_offsets = g_array_new(false, true /* clear */,
>                                          sizeof(uint32_t));
> @@ -72,6 +199,9 @@ void virt_acpi_build(VirtGuestInfo *guest_info, 
> AcpiBuildTables *tables)
>       * DSDT
>       */
>  
> +    /* DSDT is pointed to by FADT */
> +    build_dsdt(tables_blob, tables->linker, guest_info);
> +
>      /* Cleanup memory that's no longer used. */
>      g_array_free(table_offsets, true);
>  }