[Skiboot] [PATCH v8 22/24] MPIPL: Reserve memory to capture architected registers data

[Oliver O'Halloran]

On Sun, 2019-06-16 at 22:40 +0530, Vasant Hegde wrote:
> - Split SPIRAH memory to accommodate architected register ntuple.
>   Today we have 1K memory for SPIRAH and it uses 288 bytes. Lets split
>   this into two parts :
>     SPIRAH (756 bytes)
>     architected register memory (256 bytes)
> 
> - Update SPIRAH architected register ntuple
> 
> - Calculate memory required to capture architected registers data
>   Ideally we should use HDAT provided data (proc_dump_area->thread_size).
>   But we are not getting this data during boot. Hence lets reserve fixed
>   memory for architected registers data collection. This is sufficient
>   for 2 socket system. In future, if we support bigger system then we
>   have to adjust this size.
> 
> - Add architected registers destination memory to reserve-memory DT node.
> 
> Signed-off-by: Vasant Hegde <hegdevasant at linux.vnet.ibm.com>
> ---
>  core/opal-dump.c  | 30 ++++++++++++++++++++++++++++++
>  hdata/spira.c     |  7 +++++++
>  include/mem-map.h | 14 +++++++++++++-
>  skiboot.lds.S     |  5 +++++
>  4 files changed, 55 insertions(+), 1 deletion(-)
> 
> diff --git a/core/opal-dump.c b/core/opal-dump.c
> index 555908114..88b18f857 100644
> --- a/core/opal-dump.c
> +++ b/core/opal-dump.c
> @@ -16,6 +16,7 @@
>  
>  #define pr_fmt(fmt)	"DUMP: " fmt
>  
> +#include <chip.h>
>  #include <cpu.h>
>  #include <device.h>
>  #include <mem-map.h>
> @@ -31,9 +32,18 @@
>  
>  #include "hdata/spira.h"

> +/* XXX Ideally we should use HDAT provided data (proc_dump_area->thread_size).
> + *     But we are not getting this data durig boot. Hence lets reserve fixed
> + *     memory for architected registers data collection. This is sufficient
> + *     for 2 socket system. In future, if we support bigger system then we
> + *     have to adjust this size.
> + */
> +#define ARCH_REGS_DATA_SIZE		0x100000

We'll have to fix that at some point. Add a check somewhere to see if
proc_dump_area->thread_size is non-zero. If it is then we should print
a warning to say we're ignoring it so it doesn't fall through the
cracks.

>  /* Actual address of MDST and MDDT table */
>  #define MDST_TABLE_BASE		(SKIBOOT_BASE + MDST_TABLE_OFF)
>  #define MDDT_TABLE_BASE		(SKIBOOT_BASE + MDDT_TABLE_OFF)
> +#define PROC_DUMP_AREA_BASE	(SKIBOOT_BASE + PROC_DUMP_AREA_OFF)
>  
>  static struct spira_ntuple *ntuple_mdst;
>  static struct spira_ntuple *ntuple_mddt;
> @@ -213,6 +223,8 @@ static int opal_mpipl_remove_entry_mddt(bool remove_all, u8 region, u64 dest)
>  static void opal_mpipl_register(void)
>  {
>  	u64 opal_dest, opal_size;
> +	u64 arch_regs_dest, arch_regs_size;
> +	struct proc_dump_area *proc_dump = (void *)(PROC_DUMP_AREA_BASE);
>  
>  	/* Get OPAL runtime size */
>  	if (!dt_find_property(opal_node, "opal-runtime-size")) {
> @@ -229,6 +241,24 @@ static void opal_mpipl_register(void)
>  	opal_dest = SKIBOOT_BASE + opal_size;
>  	mem_reserve_fw("ibm,firmware-dump", opal_dest, opal_size);

> +	/* Calculate memory to capture CPU register data */
> +	arch_regs_dest = opal_dest + opal_size;
> +	arch_regs_size = ARCH_REGS_DATA_SIZE;
> +
> +	if (nr_chips() > 2 ) {
> +		prlog(PR_ERR, "NOT SUPPORTED ON > 2 SOCKET SYSTEM\n");
> +		prlog(PR_ERR, "INCREASE ARCHITECTED REGISTERS RESERVED MEMORY SIZE\n");
> +		assert(false);
> +	}

We have people using OPAL on four socket systems in the lab. I don't
think we've ever shipped it to customers, but it's still something that
we (as in the OPAL team) support. If the system can't do mpipl then
that's fine, just disable the feature and keep booting.

> +
> +	/* Reserve memory used to capture architected register state */
> +	mem_reserve_fw("ibm,firmware-arch-registers",
> +		       arch_regs_dest, arch_regs_size);
> +	proc_dump->alloc_addr = arch_regs_dest | HRMOR_BIT;
> +	proc_dump->alloc_size = arch_regs_size;
> +	prlog(PR_NOTICE, "Architected register dest addr : 0x%llx, "
> +	      "size : 0x%llx\n", arch_regs_dest, arch_regs_size);
> +
>  	opal_mpipl_add_entry(DUMP_REGION_OPAL_MEMORY,
>  			     SKIBOOT_BASE, opal_dest, opal_size);
>  }