Re: [PATCH v14 06/10] ACPI ERST: build the ACPI ERST table

[Eric DeVolder <eric.devolder@oracle.com>]

Michael, thanks! See inline response below, please.
eric

On 1/28/22 09:54, Michael S. Tsirkin wrote:
> On Fri, Jan 28, 2022 at 09:11:41AM -0600, Eric DeVolder wrote:
>> Michael,
>> Thanks for examining this. Inline response below.
>> eric
>>
>> On 1/27/22 18:37, Michael S. Tsirkin wrote:
>>> On Thu, Jan 27, 2022 at 04:02:07PM -0600, Eric DeVolder wrote:
>>>> Ani,
>>>> Thanks for the RB! Inline responses below.
>>>> eric
>>>>
>>>> On 1/27/22 02:36, Ani Sinha wrote:
>>>>>
>>>>>
>>>>> On Wed, 26 Jan 2022, Eric DeVolder wrote:
>>>>>
>>>>>> This builds the ACPI ERST table to inform OSPM how to communicate
>>>>>> with the acpi-erst device.
>>>>>
>>>>> There might be more optimizations possible but I think we have messaged
>>>>> this code enough. We can further rework the code if needed in subsequent
>>>>> patches once this is pushed.
>>>>>
>>>>>>
>>>>>> Signed-off-by: Eric DeVolder <eric.devolder@oracle.com>
>>>>>
>>>>> with some minor comments,
>>>>>
>>>>> Reviewed-by: Ani Sinha <ani@anisinha.ca>
>>>>>
>>>>>>     hw/acpi/erst.c | 225 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>>>>>     1 file changed, 225 insertions(+)
>>>>>>
>>>>>> diff --git a/hw/acpi/erst.c b/hw/acpi/erst.c
>>>>>> index fe9ba51..5d5a639 100644
>>>>>> --- a/hw/acpi/erst.c
>>>>>> +++ b/hw/acpi/erst.c
>>>>>> @@ -59,6 +59,27 @@
>>>>>>     #define STATUS_RECORD_STORE_EMPTY     0x04
>>>>>>     #define STATUS_RECORD_NOT_FOUND       0x05
>>>>>>
>>>>>> +/* ACPI 4.0: Table 17-19 Serialization Instructions */
>>>>>> +#define INST_READ_REGISTER                 0x00
>>>>>> +#define INST_READ_REGISTER_VALUE           0x01
>>>>>> +#define INST_WRITE_REGISTER                0x02
>>>>>> +#define INST_WRITE_REGISTER_VALUE          0x03
>>>>>> +#define INST_NOOP                          0x04
>>>>>> +#define INST_LOAD_VAR1                     0x05
>>>>>> +#define INST_LOAD_VAR2                     0x06
>>>>>> +#define INST_STORE_VAR1                    0x07
>>>>>> +#define INST_ADD                           0x08
>>>>>> +#define INST_SUBTRACT                      0x09
>>>>>> +#define INST_ADD_VALUE                     0x0A
>>>>>> +#define INST_SUBTRACT_VALUE                0x0B
>>>>>> +#define INST_STALL                         0x0C
>>>>>> +#define INST_STALL_WHILE_TRUE              0x0D
>>>>>> +#define INST_SKIP_NEXT_INSTRUCTION_IF_TRUE 0x0E
>>>>>> +#define INST_GOTO                          0x0F
>>>>>> +#define INST_SET_SRC_ADDRESS_BASE          0x10
>>>>>> +#define INST_SET_DST_ADDRESS_BASE          0x11
>>>>>> +#define INST_MOVE_DATA                     0x12
>>>>>> +
>>>>>>     /* UEFI 2.1: Appendix N Common Platform Error Record */
>>>>>>     #define UEFI_CPER_RECORD_MIN_SIZE 128U
>>>>>>     #define UEFI_CPER_RECORD_LENGTH_OFFSET 20U
>>>>>> @@ -172,6 +193,210 @@ typedef struct {
>>>>>>
>>>>>>     /*******************************************************************/
>>>>>>     /*******************************************************************/
>>>>>> +typedef struct {
>>>>>> +    GArray *table_data;
>>>>>> +    pcibus_t bar;
>>>>>> +    uint8_t instruction;
>>>>>> +    uint8_t flags;
>>>>>> +    uint8_t register_bit_width;
>>>>>> +    pcibus_t register_offset;
>>>>>> +} BuildSerializationInstructionEntry;
>>>>>> +
>>>>>> +/* ACPI 4.0: 17.4.1.2 Serialization Instruction Entries */
>>>>>> +static void build_serialization_instruction(
>>>>>> +    BuildSerializationInstructionEntry *e,
>>>>>> +    uint8_t serialization_action,
>>>>>> +    uint64_t value)
>>>>>> +{
>>>>>> +    /* ACPI 4.0: Table 17-18 Serialization Instruction Entry */
>>>>>> +    struct AcpiGenericAddress gas;
>>>>>> +    uint64_t mask;
>>>>>> +
>>>>>> +    /* Serialization Action */
>>>>>> +    build_append_int_noprefix(e->table_data, serialization_action, 1);
>>>>>> +    /* Instruction */
>>>>>> +    build_append_int_noprefix(e->table_data, e->instruction, 1);
>>>>>> +    /* Flags */
>>>>>> +    build_append_int_noprefix(e->table_data, e->flags, 1);
>>>>>> +    /* Reserved */
>>>>>> +    build_append_int_noprefix(e->table_data, 0, 1);
>>>>>> +    /* Register Region */
>>>>>> +    gas.space_id = AML_SYSTEM_MEMORY;
>>>>>> +    gas.bit_width = e->register_bit_width;
>>>>>> +    gas.bit_offset = 0;
>>>>>> +    gas.access_width = ctz32(e->register_bit_width) - 2;
>>>>>
>>>>> Should this be casted as unit8_t?
>>>> OK, done.
>>>>
>>>>>
>>>>>> +    gas.address = (uint64_t)(e->bar + e->register_offset);
>>>>>> +    build_append_gas_from_struct(e->table_data, &gas);
>>>>>> +    /* Value */
>>>>>> +    build_append_int_noprefix(e->table_data, value, 8);
>>>>>> +    /* Mask */
>>>>>> +    mask = (1ULL << (e->register_bit_width - 1) << 1) - 1;
>>>>>> +    build_append_int_noprefix(e->table_data, mask, 8);
>>>>>> +}
>>>>>> +
>>>>>> +/* ACPI 4.0: 17.4.1 Serialization Action Table */
>>>>>> +void build_erst(GArray *table_data, BIOSLinker *linker, Object *erst_dev,
>>>>>> +    const char *oem_id, const char *oem_table_id)
>>>>>> +{
>>>>>> +    /*
>>>>>> +     * Serialization Action Table
>>>>>> +     * The serialization action table must be generated first
>>>>>> +     * so that its size can be known in order to populate the
>>>>>> +     * Instruction Entry Count field.
>>>>>> +     */
>>>>>> +    GArray *table_instruction_data = g_array_new(FALSE, FALSE, sizeof(char));
>>>>>> +    pcibus_t bar0 = pci_get_bar_addr(PCI_DEVICE(erst_dev), 0);
>>>>>> +    AcpiTable table = { .sig = "ERST", .rev = 1, .oem_id = oem_id,
>>>>>> +                        .oem_table_id = oem_table_id };
>>>>>> +    /* Contexts for the different ways ACTION and VALUE are accessed */
>>>>>> +    BuildSerializationInstructionEntry rd_value_32_val = {
>>>>>> +        .table_data = table_instruction_data,
>>>>>> +        .bar = bar0,
>>>>>> +        .instruction = INST_READ_REGISTER_VALUE,
>>>>>> +        .flags = 0,
>>>>>> +        .register_bit_width = 32,
>>>>>> +        .register_offset = ERST_VALUE_OFFSET,
>>>>>> +    };
>>>>>> +    BuildSerializationInstructionEntry rd_value_32 = {
>>>>>> +        .table_data = table_instruction_data,
>>>>>> +        .bar = bar0,
>>>>>> +        .instruction = INST_READ_REGISTER,
>>>>>> +        .flags = 0,
>>>>>> +        .register_bit_width = 32,
>>>>>> +        .register_offset = ERST_VALUE_OFFSET,
>>>>>> +    };
>>>>>> +    BuildSerializationInstructionEntry rd_value_64 = {
>>>>>> +        .table_data = table_instruction_data,
>>>>>> +        .bar = bar0,
>>>>>> +        .instruction = INST_READ_REGISTER,
>>>>>> +        .flags = 0,
>>>>>> +        .register_bit_width = 64,
>>>>>> +        .register_offset = ERST_VALUE_OFFSET,
>>>>>> +    };
>>>>>> +    BuildSerializationInstructionEntry wr_value_32_val = {
>>>>>> +        .table_data = table_instruction_data,
>>>>>> +        .bar = bar0,
>>>>>> +        .instruction = INST_WRITE_REGISTER_VALUE,
>>>>>> +        .flags = 0,
>>>>>> +        .register_bit_width = 32,
>>>>>> +        .register_offset = ERST_VALUE_OFFSET,
>>>>>> +    };
>>>>>> +    BuildSerializationInstructionEntry wr_value_32 = {
>>>>>> +        .table_data = table_instruction_data,
>>>>>> +        .bar = bar0,
>>>>>> +        .instruction = INST_WRITE_REGISTER,
>>>>>> +        .flags = 0,
>>>>>> +        .register_bit_width = 32,
>>>>>> +        .register_offset = ERST_VALUE_OFFSET,
>>>>>> +    };
>>>>>> +    BuildSerializationInstructionEntry wr_value_64 = {
>>>>>> +        .table_data = table_instruction_data,
>>>>>> +        .bar = bar0,
>>>>>> +        .instruction = INST_WRITE_REGISTER,
>>>>>> +        .flags = 0,
>>>>>> +        .register_bit_width = 64,
>>>>>> +        .register_offset = ERST_VALUE_OFFSET,
>>>>>> +    };
>>>>>> +    BuildSerializationInstructionEntry wr_action = {
>>>>>> +        .table_data = table_instruction_data,
>>>>>> +        .bar = bar0,
>>>>>> +        .instruction = INST_WRITE_REGISTER_VALUE,
>>>>>> +        .flags = 0,
>>>>>> +        .register_bit_width = 32,
>>>>>> +        .register_offset = ERST_ACTION_OFFSET,
>>>>>> +    };
>>>>>
>>>>> We can probably write a macro to simply generating these structs. I see
>>>>> .bar and .flags are the same in all structs. The .bit_width can be a param
>>>>> into the macro etc.
>>>> Agree, however the request was to NOT hide the use of local variables in
>>>> macros, so while .flags is always 0, .instruction, .register_bit_width and .register_offset
>>>> would be parameters, that leaves .table_data and .bar which just need the local
>>>> variables. Is the following acceptable (which hides the use of the local variables)?
>>>
>>> You can just use assignment:
>>>
>>>      BuildSerializationInstructionEntry entry = {
>>>          .table_data = table_instruction_data,
>>>          .bar = bar0,
>>>          .flags = 0,
>>>          .register_bit_width = 32,
>>>      };
>>>      BuildSerializationInstructionEntry rd_value_32_val = entry;
>>>      rd_value_32_val.action = INST_READ_REGISTER_VALUE;
>>>      rd_value_32_val.register_offset = ERST_ACTION_OFFSET;
>>>
>>> and so on.
>>> not sure it's worth it, it's just a couple of lines.
>>>
>>
>> OK, here is the equivalent using struct assignment, is this what you were after?
>>
>>      BuildSerializationInstructionEntry base = {
>>          .table_data = table_instruction_data,
>>          .bar = bar0,
>>          .instruction = INST_WRITE_REGISTER,
>>          .flags = 0,
>>          .register_bit_width = 32,
>>          .register_offset = ERST_VALUE_OFFSET,
>>      };
>>      BuildSerializationInstructionEntry rd_value_32_val = base;
>>      rd_value_32_val.instruction = INST_READ_REGISTER_VALUE;
>>      BuildSerializationInstructionEntry rd_value_32 = base;
>>      rd_value_32.instruction = INST_READ_REGISTER;
>>      BuildSerializationInstructionEntry rd_value_64 = base;
>>      rd_value_64.instruction = INST_READ_REGISTER;
>>      rd_value_64.register_bit_width = 64;
>>      BuildSerializationInstructionEntry wr_value_32_val = base;
>>      wr_value_32_val.instruction = INST_WRITE_REGISTER_VALUE;
>>      BuildSerializationInstructionEntry wr_value_32 = base;
>>      BuildSerializationInstructionEntry wr_value_64 = base;
>>      wr_value_64.register_bit_width = 64;
>>      BuildSerializationInstructionEntry wr_action = base;
>>      wr_action.instruction = INST_WRITE_REGISTER_VALUE;
>>      wr_action.register_offset = ERST_ACTION_OFFSET;
>>
> 
> That's what I described, yes. We should have some empty lines here I
> guess. I'm ok with the original one too, there's not too much
> duplication.

Are the blank lines referring to spacing out the setup of each of the 7 accesors?
If so, I could put a one line comment between each setup? Or is a blank line also
needed?

Is it OK to post v15 with the struct assignment approach? Or would you prefer the
explicit structs (which is what I think you mean by 'the original one')?

Thanks!
eric
> 
> 
>>
>>>
>>>
>>>> #define SERIALIZATIONINSTRUCTIONCTX(name, \
>>>>       inst, bit_width, offset) \
>>>>       BuildSerializationInstructionEntry name = { \
>>>>           .table_data = table_instruction_data, \
>>>>           .bar = bar0, \
>>>>           .instruction = inst, \
>>>>           .flags = 0, \
>>>>           .register_bit_width = bit_width, \
>>>>           .register_offset = offset, \
>>>>       }
>>>>       SERIALIZATIONINSTRUCTIONCTX(rd_value_32_val,
>>>>           INST_READ_REGISTER_VALUE, 32, ERST_VALUE_OFFSET);
>>>>       SERIALIZATIONINSTRUCTIONCTX(rd_value_32,
>>>>           INST_READ_REGISTER, 32, ERST_VALUE_OFFSET);
>>>>       SERIALIZATIONINSTRUCTIONCTX(rd_value_64,
>>>>           INST_READ_REGISTER, 64, ERST_VALUE_OFFSET);
>>>>       SERIALIZATIONINSTRUCTIONCTX(wr_value_32_val,
>>>>           INST_WRITE_REGISTER_VALUE, 32, ERST_VALUE_OFFSET);
>>>>       SERIALIZATIONINSTRUCTIONCTX(wr_value_32,
>>>>           INST_WRITE_REGISTER, 32, ERST_VALUE_OFFSET);
>>>>       SERIALIZATIONINSTRUCTIONCTX(wr_value_64,
>>>>           INST_WRITE_REGISTER, 64, ERST_VALUE_OFFSET);
>>>>       SERIALIZATIONINSTRUCTIONCTX(wr_action,
>>>>           INST_WRITE_REGISTER_VALUE, 32, ERST_ACTION_OFFSET);
>>>>
>>>> These are the 7 accessors needed.
>>>
>>> not at all sure this one is worth the macro mess.
>>
>> I'm hoping to produce a v15 with the style you want.
>> eric
>>
>>>
>>>>>
>>>>>> +    unsigned action;
>>>>>> +
>>>>>> +    trace_acpi_erst_pci_bar_0(bar0);
>>>>>> +
>>>>>> +    /* Serialization Instruction Entries */
>>>>>> +    action = ACTION_BEGIN_WRITE_OPERATION;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +
>>>>>> +    action = ACTION_BEGIN_READ_OPERATION;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +
>>>>>> +    action = ACTION_BEGIN_CLEAR_OPERATION;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +
>>>>>> +    action = ACTION_END_OPERATION;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +
>>>>>> +    action = ACTION_SET_RECORD_OFFSET;
>>>>>> +    build_serialization_instruction(&wr_value_32, action, 0);
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +
>>>>>> +    action = ACTION_EXECUTE_OPERATION;
>>>>>> +    build_serialization_instruction(&wr_value_32_val, action,
>>>>>> +        ERST_EXECUTE_OPERATION_MAGIC);
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +
>>>>>> +    action = ACTION_CHECK_BUSY_STATUS;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +    build_serialization_instruction(&rd_value_32_val, action, 0x01);
>>>>>> +
>>>>>> +    action = ACTION_GET_COMMAND_STATUS;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +    build_serialization_instruction(&rd_value_32, action, 0);
>>>>>> +
>>>>>> +    action = ACTION_GET_RECORD_IDENTIFIER;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +    build_serialization_instruction(&rd_value_64, action, 0);
>>>>>> +
>>>>>> +    action = ACTION_SET_RECORD_IDENTIFIER;
>>>>>> +    build_serialization_instruction(&wr_value_64, action, 0);
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +
>>>>>> +    action = ACTION_GET_RECORD_COUNT;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +    build_serialization_instruction(&rd_value_32, action, 0);
>>>>>> +
>>>>>> +    action = ACTION_BEGIN_DUMMY_WRITE_OPERATION;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +
>>>>>> +    action = ACTION_GET_ERROR_LOG_ADDRESS_RANGE;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +    build_serialization_instruction(&rd_value_64, action, 0);
>>>>>> +
>>>>>> +    action = ACTION_GET_ERROR_LOG_ADDRESS_LENGTH;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +    build_serialization_instruction(&rd_value_64, action, 0);
>>>>>> +
>>>>>> +    action = ACTION_GET_ERROR_LOG_ADDRESS_RANGE_ATTRIBUTES;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +    build_serialization_instruction(&rd_value_32, action, 0);
>>>>>> +
>>>>>> +    action = ACTION_GET_EXECUTE_OPERATION_TIMINGS;
>>>>>> +    build_serialization_instruction(&wr_action, action, action);
>>>>>> +    build_serialization_instruction(&rd_value_64, action, 0);
>>>>>> +
>>>>>> +    /* Serialization Header */
>>>>>> +    acpi_table_begin(&table, table_data);
>>>>>> +
>>>>>> +    /* Serialization Header Size */
>>>>>> +    build_append_int_noprefix(table_data, 48, 4);
>>>>>> +
>>>>>> +    /* Reserved */
>>>>>> +    build_append_int_noprefix(table_data,  0, 4);
>>>>>> +
>>>>>> +    /*
>>>>>> +     * Instruction Entry Count
>>>>>> +     * Each instruction entry is 32 bytes
>>>>>> +     */
>>>>>> +    g_assert((table_instruction_data->len) % 32 == 0);
>>>>>> +    build_append_int_noprefix(table_data,
>>>>>> +        (table_instruction_data->len / 32), 4);
>>>>>> +
>>>>>> +    /* Serialization Instruction Entries */
>>>>>> +    g_array_append_vals(table_data, table_instruction_data->data,
>>>>>> +        table_instruction_data->len);
>>>>>> +    g_array_free(table_instruction_data, TRUE);
>>>>>> +
>>>>>> +    acpi_table_end(linker, &table);
>>>>>> +}
>>>>>> +
>>>>>> +/*******************************************************************/
>>>>>> +/*******************************************************************/
>>>>>>     static uint8_t *get_nvram_ptr_by_index(ERSTDeviceState *s, unsigned index)
>>>>>>     {
>>>>>>         uint8_t *rc = NULL;
>>>>>> --
>>>>>> 1.8.3.1
>>>>>>
>>>>>>
>>>
>