Re: [PATCH 4/7] hw/ppc: Add MDST/MDDT/MDRT table structures and offsets

[Harsh Prateek Bora <harshpb@linux.ibm.com>]

On 2/17/25 12:49, Aditya Gupta wrote:
> Add the MDST, MDDT, MDRT tables offsets and structures as per current
> skiboot upstream:
> 
>      commit bc7b85db1e7e ("opal-ci: Remove centos7")
> 
> These structures will be later populated when preserving memory regions
> for MPIPL
> 
> Signed-off-by: Aditya Gupta <adityag@linux.ibm.com>
> ---
>   hw/ppc/pnv_sbe.c | 113 +++++++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 113 insertions(+)
> 
> diff --git a/hw/ppc/pnv_sbe.c b/hw/ppc/pnv_sbe.c
> index 79818177fc36..361a3854307d 100644
> --- a/hw/ppc/pnv_sbe.c
> +++ b/hw/ppc/pnv_sbe.c

These should have been added in include/hw/ppc/pnv_sbe.h

> @@ -84,6 +84,119 @@
>   
>   static uint64_t mpipl_skiboot_base = 0x30000000 /*default SKIBOOT_BASE*/;
>   
> +/* Following offsets are copied from Skiboot source code */
> +/* Use 768 bytes for SPIRAH */
> +#define SPIRAH_OFF      0x00010000
> +#define SPIRAH_SIZE     0x300
> +
> +/* Use 256 bytes for processor dump area */
> +#define PROC_DUMP_AREA_OFF  (SPIRAH_OFF + SPIRAH_SIZE)
> +#define PROC_DUMP_AREA_SIZE 0x100
> +
> +#define PROCIN_OFF      (PROC_DUMP_AREA_OFF + PROC_DUMP_AREA_SIZE)
> +#define PROCIN_SIZE     0x800
> +
> +/* Offsets of MDST and MDDT tables from skiboot base */
> +#define MDST_TABLE_OFF      (PROCIN_OFF + PROCIN_SIZE)
> +#define MDST_TABLE_SIZE     0x400
> +
> +#define MDDT_TABLE_OFF      (MDST_TABLE_OFF + MDST_TABLE_SIZE)
> +#define MDDT_TABLE_SIZE     0x400
> +
> +#define CPU_CTL_OFF         (MDDT_TABLE_OFF + MDDT_TABLE_SIZE)
> +#define CPU_CTL_SIZE        0x2000
> +
> +/* MPIPL reserved regions (offset by skiboot_base to access) */
> +#define MDST_TABLE_BASE     (mpipl_skiboot_base + MDST_TABLE_OFF)
> +#define MDDT_TABLE_BASE     (mpipl_skiboot_base + MDDT_TABLE_OFF)
> +#define PROC_DUMP_AREA_BASE (mpipl_skiboot_base + PROC_DUMP_AREA_OFF)
> +
> +#define __packed             __attribute__((packed))
> +
> +/* Metadata to capture before triggering MPIPL */
> +struct mpipl_metadata {

CamelCase for structs? Applies for other structs below.

> +    /* Crashing PIR is required to create OPAL dump */
> +    uint32_t    crashing_pir;
> +    /* Kernel expects OPAL to presrve tag and pass it back via OPAL API */
> +    uint64_t    kernel_tag;
> +    /* Post MPIPL kernel boot memory size */
> +    uint64_t    boot_mem_size;
> +} __packed;
> +
> +/* Structure version */
> +#define OPAL_MPIPL_VERSION  0x01
> +
> +/* Preserved memory details */
> +struct opal_mpipl_region {
> +    __be64  src;
> +    __be64  dest;
> +    __be64  size;
> +};
> +
> +struct opal_mpipl_fadump {
> +    uint8_t version;
> +    uint8_t reserved[7];
> +    __be32  crashing_pir;    /* OPAL crashing CPU PIR */
> +    __be32  cpu_data_version;
> +    __be32  cpu_data_size;
> +    __be32  region_cnt;
> +    struct  opal_mpipl_region *region;
> +};
> +
> +/*
> + * This is our dump result table after MPIPL. Hostboot will write to this
> + * memory after moving memory content from source to destination memory.
> + */
> +#define MDRT_TABLE_BASE        (mpipl_skiboot_base + 0x01c00000)
> +#define MDRT_TABLE_SIZE        0x00008000
> +
> +/*
> + * This is our dump metadata area. We will use this memory to save metadata
> + * (like crashing CPU details, payload tags) before triggering MPIPL.
> + */
> +#define DUMP_METADATA_AREA_BASE    (mpipl_skiboot_base + 0x01c08000)
> +#define DUMP_METADATA_AREA_SIZE    0x8000
> +
> +/*
> + *  Memory Dump Source Table
> + *
> + * Format of this table is same as Memory Dump Source Table (MDST)
> + * defined in HDAT spec.
> + */
> +struct mdst_table {
> +    __be64  addr;
> +    uint8_t data_region;    /* DUMP_REGION_* */
> +    uint8_t dump_type;    /* DUMP_TYPE_* */
> +    __be16  reserved;
> +    __be32  size;
> +} __packed;
> +
> +/* Memory dump destination table (MDDT) */
> +struct mddt_table {
> +    __be64  addr;
> +    uint8_t data_region;
> +    uint8_t dump_type;
> +    __be16  reserved;
> +    __be32  size;
> +} __packed;

If both mdst_table and mddt_table are supposed to be same, we could have
just one mdxt_table and variable instances could be named mdst/mddt.

Thanks
Harsh

> +
> +/*
> + * Memory dump result table (MDRT)
> + *
> + * List of the memory ranges that have been included in the dump. This table is
> + * filled by hostboot and passed to OPAL on second boot. OPAL/payload will use
> + * this table to extract the dump.
> + */
> +struct mdrt_table {
> +    __be64  src_addr;
> +    __be64  dest_addr;
> +    uint8_t data_region;
> +    uint8_t dump_type;  /* unused */
> +    __be16  reserved;   /* unused */
> +    __be32  size;
> +    __be64  padding;    /* unused */
> +} __packed;
> +
>   static void pnv_sbe_set_host_doorbell(PnvSBE *sbe, uint64_t val)
>   {
>       val &= SBE_HOST_RESPONSE_MASK; /* Is this right? What does HW do? */