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

[Michael S. Tsirkin]

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.



> #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.

> > 
> > > +    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
> > > 
> > >