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

[Michael S. Tsirkin]

On Fri, Jan 28, 2022 at 10:01:18AM -0600, Eric DeVolder wrote:
> 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?

A blank line between declarations and code is usually a good idea.


> 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

I don't care either way.

> > 
> > 
> > > 
> > > > 
> > > > 
> > > > > #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
> > > > > > > 
> > > > > > > 
> > > > 
> >