Re: [Qemu-devel] [PATCH v5 2/5] nvdimm acpi: introduce patched dsm memory

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Mar 02, 2016 at 07:50:38PM +0800, Xiao Guangrong wrote:
> The dsm memory is used to save the input parameters and store
> the dsm result which is filled by QEMU.
> 
> The address of dsm memory is decided by bios and patched into
> int32 object named "MEMA"
> 
> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
> ---
>  hw/acpi/nvdimm.c | 20 +++++++++++++++++---
>  1 file changed, 17 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
> index 8568b20..90032e5 100644
> --- a/hw/acpi/nvdimm.c
> +++ b/hw/acpi/nvdimm.c
> @@ -29,6 +29,7 @@
>  #include "qemu/osdep.h"
>  #include "hw/acpi/acpi.h"
>  #include "hw/acpi/aml-build.h"
> +#include "hw/acpi/bios-linker-loader.h"
>  #include "hw/nvram/fw_cfg.h"
>  #include "hw/mem/nvdimm.h"
>  
> @@ -406,6 +407,7 @@ void nvdimm_init_acpi_state(AcpiNVDIMMState *state, MemoryRegion *io,
>  }
>  
>  #define NVDIMM_COMMON_DSM      "NCAL"
> +#define NVDIMM_ACPI_MEM_ADDR   "MEMA"
>  
>  static void nvdimm_build_common_dsm(Aml *dev)
>  {
> @@ -471,6 +473,7 @@ static void nvdimm_build_ssdt(GSList *device_list, GArray *table_offsets,
>                                GArray *table_data, GArray *linker)
>  {
>      Aml *ssdt, *sb_scope, *dev;
> +    int mem_addr_offset, nvdimm_ssdt;
>  
>      acpi_add_table(table_offsets, table_data);
>  
> @@ -500,13 +503,24 @@ static void nvdimm_build_ssdt(GSList *device_list, GArray *table_offsets,
>      nvdimm_build_nvdimm_devices(device_list, dev);
>  
>      aml_append(sb_scope, dev);
> -
>      aml_append(ssdt, sb_scope);
> +
> +    nvdimm_ssdt = table_data->len;
> +
>      /* copy AML table into ACPI tables blob and patch header there */
>      g_array_append_vals(table_data, ssdt->buf->data, ssdt->buf->len);
> +    mem_addr_offset = build_append_named_dword(table_data,
> +                                               NVDIMM_ACPI_MEM_ADDR);
> +
> +    bios_linker_loader_alloc(linker, NVDIMM_DSM_MEM_FILE, TARGET_PAGE_SIZE,
> +                             false /* high memory */);
> +    bios_linker_loader_add_pointer(linker, ACPI_BUILD_TABLE_FILE,
> +                                   NVDIMM_DSM_MEM_FILE, table_data,
> +                                   table_data->data + mem_addr_offset,
> +                                   sizeof(uint32_t));
>      build_header(linker, table_data,
> -        (void *)(table_data->data + table_data->len - ssdt->buf->len),
> -        "SSDT", ssdt->buf->len, 1, NULL, "NVDIMM");
> +        (void *)(table_data->data + nvdimm_ssdt),
> +        "SSDT", table_data->len - nvdimm_ssdt, 1, NULL, "NVDIMM");
>      free_aml_allocator();

I prefer ssdt->buf->len to table_data->len - nvdimm_ssdt.
Pls fix by a follow-up patch unless there is a respin.

>  }
>  
> -- 
> 1.8.3.1