[PATCH 2/2] kexec/ppc64: add support to parse ibm, dynamic-memory-v2 property

[Hari Bathini]

On Tuesday 20 February 2018 07:48 PM, Hari Bathini wrote:
> Add support to parse the new 'ibm,dynamic-memory-v2' property in the
> 'ibm,dynamic-reconfiguration-memory' node. This replaces the old
> 'ibm,dynamic-memory' property and is enabled in the kernel with a
> patch series that starts with commit 0c38ed6f6f0b ("powerpc/pseries:
> Enable support of ibm,dynamic-memory-v2"). All LMBs that share the same
> flags and are adjacent are grouped together in the newer version of the
> property making it compact to represent larger memory configurations.
>
> Signed-off-by: Hari Bathini <hbathini at linux.vnet.ibm.com>
> ---
>   kexec/arch/ppc64/crashdump-ppc64.c |   23 +++++++--
>   kexec/arch/ppc64/crashdump-ppc64.h |   16 +++++-
>   kexec/arch/ppc64/kexec-ppc64.c     |   35 ++++++++++----
>   kexec/fs2dt.c                      |   92 ++++++++++++++++++++++--------------
>   4 files changed, 112 insertions(+), 54 deletions(-)
>
> diff --git a/kexec/arch/ppc64/crashdump-ppc64.c b/kexec/arch/ppc64/crashdump-ppc64.c
> index bc9f948..50e3853 100644
> --- a/kexec/arch/ppc64/crashdump-ppc64.c
> +++ b/kexec/arch/ppc64/crashdump-ppc64.c
> @@ -39,6 +39,10 @@
>   #define DEVTREE_CRASHKERNEL_BASE "/proc/device-tree/chosen/linux,crashkernel-base"
>   #define DEVTREE_CRASHKERNEL_SIZE "/proc/device-tree/chosen/linux,crashkernel-size"
>
> +unsigned int num_of_lmb_sets;
> +unsigned int is_dyn_mem_v2;
> +uint64_t lmb_size;
> +
>   static struct crash_elf_info elf_info64 =
>   {
>   	class: ELFCLASS64,
> @@ -127,6 +131,7 @@ static int get_dyn_reconf_crash_memory_ranges(void)
>   {
>   	uint64_t start, end;
>   	uint64_t startrange, endrange;
> +	uint64_t size;
>   	char fname[128], buf[32];
>   	FILE *file;
>   	unsigned int i;
> @@ -135,6 +140,8 @@ static int get_dyn_reconf_crash_memory_ranges(void)
>
>   	strcpy(fname, "/proc/device-tree/");
>   	strcat(fname, "ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory");
> +	if (is_dyn_mem_v2)
> +		strcat(fname, "-v2");
>   	if ((file = fopen(fname, "r")) == NULL) {
>   		perror(fname);
>   		return -1;
> @@ -142,8 +149,9 @@ static int get_dyn_reconf_crash_memory_ranges(void)
>
>   	fseek(file, 4, SEEK_SET);
>   	startrange = endrange = 0;
> -	for (i = 0; i < num_of_lmbs; i++) {
> -		if ((n = fread(buf, 1, 24, file)) < 0) {
> +	size = lmb_size;
> +	for (i = 0; i < num_of_lmb_sets; i++) {
> +		if ((n = fread(buf, 1, LMB_ENTRY_SIZE, file)) < 0) {
>   			perror(fname);
>   			fclose(file);
>   			return -1;
> @@ -156,8 +164,15 @@ static int get_dyn_reconf_crash_memory_ranges(void)
>   			return -1;
>   		}
>
> -		start = be64_to_cpu(((uint64_t *)buf)[DRCONF_ADDR]);
> -		end = start + lmb_size;
> +		/*
> +		 * If the property is ibm,dynamic-memory-v2, the first 4 bytes
> +		 * tell the number of sequential LMBs in this entry.
> +		 */
> +		if (is_dyn_mem_v2)
> +			size = be32_to_cpu(((unsigned int *)buf)[0]) * lmb_size;
> +
> +		start = be64_to_cpu(*((uint64_t *)&buf[DRCONF_ADDR]));
> +		end = start + size;
>   		if (start == 0 && end >= (BACKUP_SRC_END + 1))
>   			start = BACKUP_SRC_END + 1;
>
> diff --git a/kexec/arch/ppc64/crashdump-ppc64.h b/kexec/arch/ppc64/crashdump-ppc64.h
> index 42ccc31..87beb39 100644
> --- a/kexec/arch/ppc64/crashdump-ppc64.h
> +++ b/kexec/arch/ppc64/crashdump-ppc64.h
> @@ -34,10 +34,18 @@ extern unsigned int rtas_size;
>   extern uint64_t opal_base;
>   extern uint64_t opal_size;
>
> -uint64_t lmb_size;
> -unsigned int num_of_lmbs;

This might probably break compilation on other architectures like arm64 
& mips.
Will check and post v2..

- Hari