[PATCH 1/2 kexec-tools] ppc64: new relocatble kernel activation ABI

Milton Miller
2008-10-22T20:39:29Z

The updates kexec-tools to match the kernel after the patches

"kexec exit should not use magic numbers" and

"better flag for running relocatable" are applied.

Signed-off-by: Milton Miller <miltonm@bga.com>
---
Still proposed change

Index: kexec-tools/purgatory/arch/ppc64/v2wrap.S
===================================================================
--- kexec-tools.orig/purgatory/arch/ppc64/v2wrap.S 2008-10-22 06:14:44.000000000 -0500
+++ kexec-tools/purgatory/arch/ppc64/v2wrap.S 2008-10-22 06:14:48.000000000 -0500
@@ -45,11 +45,13 @@
oris rn,rn,name##@h; \
ori rn,rn,name##@l

-#define KDUMP_SIGNATURE 0xfeed1234
-
.machine ppc64
.globl purgatory_start
purgatory_start: b master
+ .org purgatory_start + 0x5c # ABI: possible run_at_load flag at 0x5c
+run_at_load:
+ .long 0
+ .size run_at_load, . - run_at_load
.org purgatory_start + 0x60 # ABI: slaves start at 60 with r3=phys
slave: b $
.org purgatory_start + 0x100 # ABI: end of copied region
@@ -65,7 +67,6 @@ master:
isync
mr 17,3 # save cpu id to r17
mr 15,4 # save physical address in reg15
- mr 18,6 # save kdump flag in reg18

LOADADDR(6,my_toc)
ld 2,0(6) #setup toc
@@ -96,14 +97,6 @@ master:
mtctr 4 # prepare branch too
mr 3,16 # restore dt address

- LOADADDR(6,KDUMP_SIGNATURE)
- cmpd 18,6
- bne regular
- li 7,1
- std 7,24(4) # mark kdump flag at kernel
-regular:
- lwz 7,0(4) # get the first instruction that we stole
- stw 7,0(0) # and put it in the slave loop at 0
# skip cache flush, do we care?

bctr # start kernel
Index: kexec-tools/kexec/arch/ppc64/crashdump-ppc64.h
===================================================================
--- kexec-tools.orig/kexec/arch/ppc64/crashdump-ppc64.h 2008-10-22 06:14:44.000000000 -0500
+++ kexec-tools/kexec/arch/ppc64/crashdump-ppc64.h 2008-10-22 06:14:48.000000000 -0500
@@ -23,6 +23,8 @@ void add_usable_mem_rgns(unsigned long l
#define _ALIGN_UP(addr,size) (((addr)+((size)-1))&(~((size)-1)))
#define _ALIGN_DOWN(addr,size) ((addr)&(~((size)-1)))

+#define KERNEL_RUN_AT_ZERO_MAGIC 0x72756e30 /* "run0" */
+
extern uint64_t crash_base;
extern uint64_t crash_size;
extern unsigned int rtas_base;
Index: kexec-tools/kexec/arch/ppc64/kexec-elf-ppc64.c
===================================================================
--- kexec-tools.orig/kexec/arch/ppc64/kexec-elf-ppc64.c 2008-10-22 06:14:44.000000000 -0500
+++ kexec-tools/kexec/arch/ppc64/kexec-elf-ppc64.c 2008-10-22 06:14:48.000000000 -0500
@@ -93,6 +93,7 @@ int elf_ppc64_load(int argc, char **argv
uint64_t my_stack, my_backup_start;
uint64_t toc_addr;
unsigned int slave_code[256/sizeof (unsigned int)], master_entry;
+ unsigned int run_at_load;

#define OPT_APPEND (OPT_ARCH_MAX+0)
#define OPT_RAMDISK (OPT_ARCH_MAX+1)
@@ -307,6 +308,18 @@ int elf_ppc64_load(int argc, char **argv
my_backup_start = info->backup_start;
elf_rel_set_symbol(&info->rhdr, "backup_start",
&my_backup_start, sizeof(my_backup_start));
+
+ /* Tell relocatable kernel to run at load address
+ * via word before slave code in purgatory
+ */
+
+ elf_rel_get_symbol(&info->rhdr, "run_at_load", &run_at_load,
+ sizeof(run_at_load));
+ if (run_at_load == KERNEL_RUN_AT_ZERO_MAGIC)
+ run_at_load = 1;
+ /* else it should be a fixed offset image */
+ elf_rel_set_symbol(&info->rhdr, "run_at_load", &run_at_load,
+ sizeof(run_at_load));
}

/* Set stack address */
@@ -325,10 +338,13 @@ int elf_ppc64_load(int argc, char **argv
my_backup_start = 0;
my_stack = 0;
toc_addr = 0;
+ run_at_load = 0;

elf_rel_get_symbol(&info->rhdr, "kernel", &my_kernel, sizeof(my_kernel));
elf_rel_get_symbol(&info->rhdr, "dt_offset", &my_dt_offset,
sizeof(my_dt_offset));
+ elf_rel_get_symbol(&info->rhdr, "run_at_load", &run_at_load,
+ sizeof(run_at_load));
elf_rel_get_symbol(&info->rhdr, "panic_kernel", &my_panic_kernel,
sizeof(my_panic_kernel));
elf_rel_get_symbol(&info->rhdr, "backup_start", &my_backup_start,
@@ -341,6 +357,7 @@ int elf_ppc64_load(int argc, char **argv
fprintf(stderr, "kernel is %llx\n", (unsigned long long)my_kernel);
fprintf(stderr, "dt_offset is %llx\n",
(unsigned long long)my_dt_offset);
+ fprintf(stderr, "run_at_load flag is %x\n", run_at_load);
fprintf(stderr, "panic_kernel is %x\n", my_panic_kernel);
fprintf(stderr, "backup_start is %llx\n",
(unsigned long long)my_backup_start);