[Skiboot] [PATCH v7 22/22] fadump: Save crashing cpu data

[Michael Neuling]

On Sat, 2019-04-13 at 14:45 +0530, Vasant Hegde wrote:
> Crashing CPU detail is required to get proper backtrace from core file.
> Save crashing CPU data before triggering MPIPL. During MPIPL boot
> pass this detail to Host Linux via device tree.

This seems to be just saving *which* CPU crashing (via the PIR). 

This could made clearer in the commit message and subject.

> Signed-off-by: Vasant Hegde <hegdevasant at linux.vnet.ibm.com>
> ---
>  core/opal-dump.c    | 9 +++++++++
>  hdata/spira.c       | 8 ++++++++
>  hw/sbe-p9.c         | 4 ++++
>  include/mem-map.h   | 9 ++++++++-
>  include/opal-dump.h | 8 ++++++++
>  5 files changed, 37 insertions(+), 1 deletion(-)
> 
> diff --git a/core/opal-dump.c b/core/opal-dump.c
> index f06739937..9d3e56b7e 100644
> --- a/core/opal-dump.c
> +++ b/core/opal-dump.c
> @@ -16,6 +16,7 @@
>  
>  #define pr_fmt(fmt)	"DUMP: " fmt
>  
> +#include <cpu.h>
>  #include <device.h>
>  #include <mem-map.h>
>  #include <mem_region.h>
> @@ -349,6 +350,14 @@ static void adjust_opal_dump_size(struct dt_node
> *dump_node)
>  	add_dump_reserve_node(dump_node);
>  }
>  
> +void opal_dump_save_metadata(void)
> +{
> +	struct dump_metadata *m = (struct dump_metadata
> *)(DUMP_METADATA_AREA_BASE);
> +
> +	m->crashing_cpu = this_cpu()->pir;
> +	prlog(PR_NOTICE, "Crashing CPU = 0x%x\n", m->crashing_cpu);
> +}
> +
>  void opal_dump_init(void)
>  {
>  	struct dt_node *dump_node;
> diff --git a/hdata/spira.c b/hdata/spira.c
> index 84a0094f1..e1b544da0 100644
> --- a/hdata/spira.c
> +++ b/hdata/spira.c
> @@ -1118,6 +1118,10 @@ static void opal_dump_add_result_table(const struct
> iplparams_iplparams *p)
>  	struct fadump_section *fadump_section;
>  	struct fadump *result_table;
>  	struct dt_node *dump_node;
> +	struct dump_metadata *m;
> +
> +	m = (struct dump_metadata *)(DUMP_METADATA_AREA_BASE -
> +				     SKIBOOT_BASE + DUMP_DEST_SKIBOOT_BASE);
>  
>  	dump_node = dt_find_by_path(opal_node, "dump");
>  	if (!dump_node)
> @@ -1192,6 +1196,10 @@ static void opal_dump_add_result_table(const struct
> iplparams_iplparams *p)
>  	/* Add architected register data to result-table */
>  	opal_dump_add_arch_regs(dump_node, result_table, &j);
>  
> +	/* Fill crashing CPU details */
> +	result_table->crashing_cpu = cpu_to_be32(m->crashing_cpu);
> +	prlog(PR_NOTICE, "DUMP: Crashed cpu = 0x%x\n", m->crashing_cpu);
> +
>  	result_table->section_count = cpu_to_be16(j);
>  	/* Actual property size */
>  	prop_size = sizeof(struct fadump) + (j * sizeof(struct fadump_section));
> diff --git a/hw/sbe-p9.c b/hw/sbe-p9.c
> index bf3ca9e68..ac890a2d9 100644
> --- a/hw/sbe-p9.c
> +++ b/hw/sbe-p9.c
> @@ -50,6 +50,7 @@
>  #include <errorlog.h>
>  #include <lock.h>
>  #include <opal.h>
> +#include <opal-dump.h>
>  #include <sbe-p9.h>
>  #include <skiboot.h>
>  #include <timebase.h>
> @@ -971,6 +972,9 @@ void p9_sbe_terminate(void)
>  		return;
>  	}
>  
> +	/* Save crashing CPU details */
> +	opal_dump_save_metadata();
> +
>  	dt_for_each_compatible(dt_root, xn, "ibm,xscom") {
>  		chip_id = dt_get_chip_id(xn);
>  
> diff --git a/include/mem-map.h b/include/mem-map.h
> index 0cb4d5da4..a4b74f9d9 100644
> --- a/include/mem-map.h
> +++ b/include/mem-map.h
> @@ -119,7 +119,14 @@
>   * memory after moving memory content from source to destination memory.
>   */
>  #define MDRT_TABLE_BASE		(SKIBOOT_BASE + 0x01c00000)
> -#define MDRT_TABLE_SIZE		0x00010000
> +#define MDRT_TABLE_SIZE		0x0000f000
> +
> +/*
> + * This is our dump meta data area. We will use this memory to save
> + * crashing CPU details before triggering MPIPL.
> + */
> +#define DUMP_METADATA_AREA_BASE	(SKIBOOT_BASE + 0x01c0f000)
> +#define DUMP_METADATA_AREA_SIZE	0x1000
>  
>  /* Total size of the above area
>   *
> diff --git a/include/opal-dump.h b/include/opal-dump.h
> index d71691e13..a12b4c5c2 100644
> --- a/include/opal-dump.h
> +++ b/include/opal-dump.h
> @@ -124,7 +124,15 @@ struct proc_reg_data {
>  } __packed;
>  
>  
> +/* Meta data to capture before triggering MPIPL */
> +struct dump_metadata {
> +	uint32_t crashing_cpu;
> +};
> +
>  /* init opal dump */
>  extern void opal_dump_init(void);
>  
> +/* Save metadata before triggering MPIPL */
> +extern void opal_dump_save_metadata(void);
> +
>  #endif	/* __OPAL_DUMP_H */