On Mon Feb 17, 2025 at 5:17 PM AEST, Aditya Gupta wrote:
> Platform (ie. QEMU) is expected to pass few device tree properties for
> details for fadump:
>
> * "ibm,configure-kernel-dump": RTAS call for fadump
> * "ibm,configure-kernel-dump-sizes": Space required to store dump data
> for firmware provided dump sections (ie. CPU & HPTE regions)
> * "ibm,configure-kernel-dump-version": Versions of fadump supported
> * "ibm,kernel-dump": Contains the Fadump Memory Structure on a fadump
> boot
>
> Implement passing configure-kernel-dump-sizes, and
> configure-kernel-dump-version device tree properties, irrespective of
> whether it's a fadump boot or not, so that kernel can reserve memory to
> store the firmware provided dump sections in case of a crash
>
> Also, in case of a fadump boot, pass the fadump memory structure to the
> kernel in "ibm,kernel-dump" device tree property.
>
> Signed-off-by: Aditya Gupta <adit...@linux.ibm.com>
> ---
> hw/ppc/spapr.c | 62 ++++++++++++++++++++++++++++++++++++++++++
> include/hw/ppc/spapr.h | 2 ++
> 2 files changed, 64 insertions(+)
>
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index f3a4b4235d43..3602e5b5d18d 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -897,9 +897,27 @@ static int spapr_dt_rng(void *fdt)
> static void spapr_dt_rtas(SpaprMachineState *spapr, void *fdt)
> {
You might be able to add a spapr_dt_rtas_fadump() function
and do it there to help keep functions small?
Thanks,
Nick
> MachineState *ms = MACHINE(spapr);
> + MachineClass *mc = MACHINE_GET_CLASS(ms);
> int rtas;
> GString *hypertas = g_string_sized_new(256);
> GString *qemu_hypertas = g_string_sized_new(256);
> + uint32_t max_possible_cpus = mc->possible_cpu_arch_ids(ms)->len;
> + uint64_t fadump_cpu_state_size = 0;
> + uint16_t fadump_versions[2] = {
> + FADUMP_VERSION /* min supported version */,
> + FADUMP_VERSION /* max supported version */
> + };
> + uint32_t fadump_rgn_sizes[2][3] = {
> + {
> + cpu_to_be32(FADUMP_CPU_STATE_DATA),
> + 0, 0 /* Calculated later */
> + },
> + {
> + cpu_to_be32(FADUMP_HPTE_REGION),
> + 0, 0 /* HPTE region not implemented */
> + }
> + };
> +
> uint32_t lrdr_capacity[] = {
> 0,
> 0,
> @@ -1006,6 +1024,50 @@ static void spapr_dt_rtas(SpaprMachineState *spapr,
> void *fdt)
> _FDT(fdt_setprop(fdt, rtas, "ibm,lrdr-capacity",
> lrdr_capacity, sizeof(lrdr_capacity)));
>
> + /*
> + * CPU State Data contains multiple fields such as header, num_cpus and
> + * register entries
> + *
> + * Calculate the maximum CPU State Data size, according to maximum
> + * possible CPUs the QEMU VM can have
> + */
> + /* Reg save header */
> + fadump_cpu_state_size += sizeof(struct rtas_fadump_reg_save_area_header);
> +
> + /* Num_cpus */
> + fadump_cpu_state_size += sizeof(__be32);
> +
> + /* Register Entries */
> + fadump_cpu_state_size += max_possible_cpus *
> + FADUMP_NUM_PER_CPU_REGS *
> + sizeof(struct rtas_fadump_reg_entry);
> +
> + /* Set maximum size for CPU state data region */
> + assert(fadump_rgn_sizes[0][0] == cpu_to_be32(FADUMP_CPU_STATE_DATA));
> +
> + /* Upper 32 bits of size, usually 0 */
> + fadump_rgn_sizes[0][1] = cpu_to_be32(fadump_cpu_state_size >> 32);
> +
> + /* Lower 32 bits of size */
> + fadump_rgn_sizes[0][2] = cpu_to_be32(fadump_cpu_state_size & 0xffffffff);
> +
> + /* Add device tree properties required from platform for fadump */
> + _FDT((fdt_setprop(fdt, rtas, "ibm,configure-kernel-dump-version",
> + fadump_versions, sizeof(fadump_versions))));
> + _FDT((fdt_setprop(fdt, rtas, "ibm,configure-kernel-dump-sizes",
> + fadump_rgn_sizes, sizeof(fadump_rgn_sizes))));
> +
> + if (is_next_boot_fadump) {
> + struct rtas_fadump_mem_struct *fdm =
> + &fadump_metadata.registered_fdm;
> +
> + uint64_t fdm_size =
> + sizeof(struct rtas_fadump_section_header) +
> + (be16_to_cpu(fdm->header.dump_num_sections) *
> + sizeof(struct rtas_fadump_section));
> +
> + _FDT((fdt_setprop(fdt, rtas, "ibm,kernel-dump", fdm, fdm_size)));
> + }
> spapr_dt_rtas_tokens(fdt, rtas);
> }
>
> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> index 0e8002bad9e0..fa63008e57ec 100644
> --- a/include/hw/ppc/spapr.h
> +++ b/include/hw/ppc/spapr.h
> @@ -928,6 +928,8 @@ static inline uint64_t fadump_gpr_id_to_u64(uint32_t
> gpr_id)
> return val;
> }
>
> +extern bool is_next_boot_fadump;
> +
> struct fadump_metadata {
> bool fadump_registered;
> bool fadump_dump_active;
