Re: [Qemu-devel] [PATCH 5/6] nvdimm acpi: let qemu handle _DSM method

[Igor Mammedov]

On Tue,  5 Jan 2016 02:52:07 +0800
Xiao Guangrong <address@hidden> wrote:

> If dsm memory is successfully patched, we let qemu fully emulate
> the dsm method
> 
> This patch saves _DSM input parameters into dsm memory, tell dsm
> memory address to QEMU, then fetch the result from the dsm memory
you also need to add NVDR._CRS method that would report
resources used by operation regions.

NVDIMM_COMMON_DSM - probably should be serialized, otherwise
there is a race risk, when several callers would write to
control region.


> 
> Signed-off-by: Xiao Guangrong <address@hidden>
> ---
>  hw/acpi/aml-build.c         |  27 ++++++++++
>  hw/acpi/nvdimm.c            | 124 
> ++++++++++++++++++++++++++++++++++++++++++--
>  include/hw/acpi/aml-build.h |   2 +
>  3 files changed, 150 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c
> index 677c1a6..e65171f 100644
> --- a/hw/acpi/aml-build.c
> +++ b/hw/acpi/aml-build.c
> @@ -1013,6 +1013,19 @@ Aml *create_field_common(int opcode, Aml *srcbuf, Aml 
> *index, const char *name)
>      return var;
>  }
>  
> +/* ACPI 1.0b: 16.2.5.2 Named Objects Encoding: DefCreateField */
> +Aml *aml_create_field(Aml *srcbuf, Aml *index, Aml *len, const char *name)
> +{
> +    Aml *var = aml_alloc();
> +    build_append_byte(var->buf, 0x5B); /* ExtOpPrefix */
> +    build_append_byte(var->buf, 0x13); /* CreateFieldOp */
> +    aml_append(var, srcbuf);
> +    aml_append(var, index);
> +    aml_append(var, len);
> +    build_append_namestring(var->buf, "%s", name);
> +    return var;
> +}
> +
>  /* ACPI 1.0b: 16.2.5.2 Named Objects Encoding: DefCreateDWordField */
>  Aml *aml_create_dword_field(Aml *srcbuf, Aml *index, const char *name)
>  {
> @@ -1439,6 +1452,20 @@ Aml *aml_alias(const char *source_object, const char 
> *alias_object)
>      return var;
>  }
>  
> +/* ACPI 1.0b: 16.2.5.4 Type 2 Opcodes Encoding: DefConcat */
> +Aml *aml_concatenate(Aml *source1, Aml *source2, Aml *target)
> +{
> +    Aml *var = aml_opcode(0x73 /* ConcatOp */);
> +    aml_append(var, source1);
> +    aml_append(var, source2);
> +
> +    if (target) {
> +        aml_append(var, target);
> +    }
> +
> +    return var;
> +}
> +
>  void
>  build_header(GArray *linker, GArray *table_data,
>               AcpiTableHeader *h, const char *sig, int len, uint8_t rev,
> diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
> index a72104c..dfccbc0 100644
> --- a/hw/acpi/nvdimm.c
> +++ b/hw/acpi/nvdimm.c
> @@ -369,6 +369,24 @@ static void nvdimm_build_nfit(GSList *device_list, 
> GArray *table_offsets,
>      g_array_free(structures, true);
>  }
>  
> +struct NvdimmDsmIn {
> +    uint32_t handle;
> +    uint32_t revision;
> +    uint32_t function;
> +   /* the remaining size in the page is used by arg3. */
> +    union {
> +        uint8_t arg3[0];
> +    };
> +} QEMU_PACKED;
> +typedef struct NvdimmDsmIn NvdimmDsmIn;
> +
> +struct NvdimmDsmOut {
> +    /* the size of buffer filled by QEMU. */
> +    uint32_t len;
> +    uint8_t data[0];
> +} QEMU_PACKED;
> +typedef struct NvdimmDsmOut NvdimmDsmOut;
> +
>  static uint64_t
>  nvdimm_dsm_read(void *opaque, hwaddr addr, unsigned size)
>  {
> @@ -408,11 +426,21 @@ void nvdimm_init_acpi_state(AcpiNVDIMMState *state, 
> MemoryRegion *io,
>  
>  static void nvdimm_build_common_dsm(Aml *dev)
>  {
> -    Aml *method, *ifctx, *function;
> +    Aml *method, *ifctx, *function, *unpatched, *field, *high_dsm_mem;
> +    Aml *result_size, *dsm_mem;
>      uint8_t byte_list[1];
>  
>      method = aml_method(NVDIMM_COMMON_DSM, 4, AML_NOTSERIALIZED);
>      function = aml_arg(2);
> +    dsm_mem = aml_arg(3);
> +
> +    aml_append(method, aml_store(aml_call0(NVDIMM_GET_DSM_MEM), dsm_mem));
> +
> +    /*
> +     * do not support any method if DSM memory address has not been
> +     * patched.
> +     */
> +    unpatched = aml_if(aml_equal(dsm_mem, aml_int64(0x0)));
>  
>      /*
>       * function 0 is called to inquire what functions are supported by
> @@ -421,12 +449,102 @@ static void nvdimm_build_common_dsm(Aml *dev)
>      ifctx = aml_if(aml_equal(function, aml_int(0)));
>      byte_list[0] = 0 /* No function Supported */;
>      aml_append(ifctx, aml_return(aml_buffer(1, byte_list)));
> -    aml_append(method, ifctx);
> +    aml_append(unpatched, ifctx);
>  
>      /* No function is supported yet. */
>      byte_list[0] = 1 /* Not Supported */;
> -    aml_append(method, aml_return(aml_buffer(1, byte_list)));
> +    aml_append(unpatched, aml_return(aml_buffer(1, byte_list)));
> +    aml_append(method, unpatched);
> +
> +    /* map DSM memory and IO into ACPI namespace. */
> +    aml_append(method, aml_operation_region("NPIO", AML_SYSTEM_IO,
> +               aml_int(NVDIMM_ACPI_IO_BASE), NVDIMM_ACPI_IO_LEN));
> +    aml_append(method, aml_operation_region("NRAM", AML_SYSTEM_MEMORY,
> +                                            dsm_mem, TARGET_PAGE_SIZE));
> +
> +    /*
> +     * DSM notifier:
> +     * LNTF: write the low 32 bits of DSM memory.
> +     * HNTF: write the high 32 bits of DSM memory and notify QEMU to
> +     *       emulate the access.
> +     *
> +     * They are IO ports so that accessing them will cause VM-exit, the
> +     * control will be transferred to QEMU.
> +     */
> +    field = aml_field("NPIO", AML_DWORD_ACC, AML_NOLOCK, AML_PRESERVE);
> +    aml_append(field, aml_named_field("LNTF",
> +               sizeof(uint32_t) * BITS_PER_BYTE));
> +    aml_append(field, aml_named_field("HNTF",
> +               sizeof(uint32_t) * BITS_PER_BYTE));
> +    aml_append(method, field);
>  
> +    /*
> +     * DSM input:
> +     * @HDLE: store device's handle, it's zero if the _DSM call happens
> +     *        on NVDIMM Root Device.
> +     * @REVS: store the Arg1 of _DSM call.
> +     * @FUNC: store the Arg2 of _DSM call.
> +     * @ARG3: store the Arg3 of _DSM call.
> +     *
> +     * They are RAM mapping on host so that these accesses never cause
> +     * VM-EXIT.
> +     */
> +    field = aml_field("NRAM", AML_DWORD_ACC, AML_NOLOCK, AML_PRESERVE);
> +    aml_append(field, aml_named_field("HDLE",
> +               sizeof(typeof_field(NvdimmDsmIn, handle)) * BITS_PER_BYTE));
> +    aml_append(field, aml_named_field("REVS",
> +               sizeof(typeof_field(NvdimmDsmIn, revision)) * BITS_PER_BYTE));
> +    aml_append(field, aml_named_field("FUNC",
> +               sizeof(typeof_field(NvdimmDsmIn, function)) * BITS_PER_BYTE));
> +    aml_append(field, aml_named_field("ARG3",
> +               (TARGET_PAGE_SIZE - offsetof(NvdimmDsmIn, arg3)) *
> +                     BITS_PER_BYTE));
> +    aml_append(method, field);
> +
> +    /*
> +     * DSM output:
> +     * @RLEN: the size of the buffer filled by QEMU.
> +     * @ODAT: the buffer QEMU uses to store the result.
> +     *
> +     * Since the page is reused by both input and out, the input data
> +     * will be lost after storing new result into @ODAT.
> +    */
> +    field = aml_field("NRAM", AML_DWORD_ACC, AML_NOLOCK, AML_PRESERVE);
> +    aml_append(field, aml_named_field("RLEN",
> +               sizeof(typeof_field(NvdimmDsmOut, len)) * BITS_PER_BYTE));
> +    aml_append(field, aml_named_field("ODAT",
> +               (TARGET_PAGE_SIZE - offsetof(NvdimmDsmOut, data)) *
> +                     BITS_PER_BYTE));
> +    aml_append(method, field);
> +
> +    /*
> +     * Currently no function is supported for both root device and NVDIMM
> +     * devices, let's temporarily set handle to 0x0 at this time.
> +     */
> +    aml_append(method, aml_store(aml_int(0x0), aml_name("HDLE")));
> +    aml_append(method, aml_store(aml_arg(1), aml_name("REVS")));
> +    aml_append(method, aml_store(aml_arg(2), aml_name("FUNC")));
> +
> +    /*
> +     * tell QEMU about the real address of DSM memory, then QEMU begins
> +     * to emulate the method and fills the result to DSM memory.
> +     */
> +    aml_append(method, aml_store(dsm_mem, aml_name("LNTF")));
> +    high_dsm_mem = aml_shiftright(dsm_mem,
> +                                  aml_int(sizeof(uint32_t) * BITS_PER_BYTE),
> +                                  NULL);
> +    aml_append(method, aml_store(high_dsm_mem, aml_name("HNTF")));
> +
> +    result_size = aml_local(1);
> +    aml_append(method, aml_store(aml_name("RLEN"), result_size));
> +    aml_append(method, aml_store(aml_shiftleft(result_size, aml_int(3)),
> +                                 result_size));
> +    aml_append(method, aml_create_field(aml_name("ODAT"), aml_int(0),
> +                                        result_size, "OBUF"));
> +    aml_append(method, aml_name_decl("ZBUF", aml_buffer(0, NULL)));
> +    aml_append(method, aml_concatenate(aml_name("ZBUF"), aml_name("OBUF"),
> +                                       aml_arg(6)));
> +    aml_append(method, aml_return(aml_arg(6)));
>      aml_append(dev, method);
>  }
>  
> diff --git a/include/hw/acpi/aml-build.h b/include/hw/acpi/aml-build.h
> index a8d8f3b..6c1816e 100644
> --- a/include/hw/acpi/aml-build.h
> +++ b/include/hw/acpi/aml-build.h
> @@ -344,6 +344,7 @@ Aml *aml_mutex(const char *name, uint8_t sync_level);
>  Aml *aml_acquire(Aml *mutex, uint16_t timeout);
>  Aml *aml_release(Aml *mutex);
>  Aml *aml_alias(const char *source_object, const char *alias_object);
> +Aml *aml_create_field(Aml *srcbuf, Aml *index, Aml *len, const char *name);
>  Aml *aml_create_dword_field(Aml *srcbuf, Aml *index, const char *name);
>  Aml *aml_create_qword_field(Aml *srcbuf, Aml *index, const char *name);
>  Aml *aml_varpackage(uint32_t num_elements);
> @@ -351,6 +352,7 @@ Aml *aml_touuid(const char *uuid);
>  Aml *aml_unicode(const char *str);
>  Aml *aml_derefof(Aml *arg);
>  Aml *aml_sizeof(Aml *arg);
> +Aml *aml_concatenate(Aml *source1, Aml *source2, Aml *target);
>  
>  void
>  build_header(GArray *linker, GArray *table_data,