[PATCH] powerpc: Parse crashkernel= parameter in first kernel

This patch adds code to parse and setup the crash kernel resource in the
first kernel. PPC64 ignores the @x part, we always run at 32 MB.

Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 9aac77ca3167ba9247f1dd218f78d4928f01d5cf..fddc9c13bff50b3328e215ab2e8fe83d6d21a004 100644 (file)
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -29,6 +29,7 @@
 #include <linux/initrd.h>
 #include <linux/bitops.h>
 #include <linux/module.h>
+#include <linux/kexec.h>
 
 #include <asm/prom.h>
 #include <asm/rtas.h>
@@ -1198,6 +1199,16 @@ static int __init early_init_dt_scan_chosen(unsigned long node,
        }
 #endif /* CONFIG_PPC_RTAS */
 
+#ifdef CONFIG_KEXEC
+       lprop = (u64*)of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
+       if (lprop)
+               crashk_res.start = *lprop;
+
+       lprop = (u64*)of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
+       if (lprop)
+               crashk_res.end = crashk_res.start + *lprop - 1;
+#endif
+
        /* break now */
        return 1;
 }

diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index 369e1a6cdd40ad03655474a52c849d204b1c1cbd..2ae860c306d75b427b49ffebda8e86b1d80555d1 100644 (file)
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -192,6 +192,11 @@ static unsigned long __initdata alloc_bottom;
 static unsigned long __initdata rmo_top;
 static unsigned long __initdata ram_top;
 
+#ifdef CONFIG_KEXEC
+static unsigned long __initdata prom_crashk_base;
+static unsigned long __initdata prom_crashk_size;
+#endif
+
 static struct mem_map_entry __initdata mem_reserve_map[MEM_RESERVE_MAP_SIZE];
 static int __initdata mem_reserve_cnt;
 
@@ -590,6 +595,34 @@ static void __init early_cmdline_parse(void)
                RELOC(prom_memory_limit) = ALIGN(RELOC(prom_memory_limit), 0x1000000);
 #endif
        }
+
+#ifdef CONFIG_KEXEC
+       /*
+        * crashkernel=size@addr specifies the location to reserve for
+        * crash kernel.
+        */
+       opt = strstr(RELOC(prom_cmd_line), RELOC("crashkernel="));
+       if (opt) {
+               opt += 12;
+               RELOC(prom_crashk_size) = prom_memparse(opt, &opt);
+
+               if (ALIGN(RELOC(prom_crashk_size), 0x1000000) !=
+                       RELOC(prom_crashk_size)) {
+                       prom_printf("Warning: crashkernel size is not "
+                                       "aligned to 16MB\n");
+               }
+
+               /*
+                * At present, the crash kernel always run at 32MB.
+                * Just ignore whatever user passed.
+                */
+               RELOC(prom_crashk_base) = 0x2000000;
+               if (*opt == '@') {
+                       prom_printf("Warning: PPC64 kdump kernel always runs "
+                                       "at 32 MB\n");
+               }
+       }
+#endif
 }
 
 #ifdef CONFIG_PPC_PSERIES
@@ -1011,6 +1044,12 @@ static void __init prom_init_mem(void)
        prom_printf("  alloc_top_hi : %x\n", RELOC(alloc_top_high));
        prom_printf("  rmo_top      : %x\n", RELOC(rmo_top));
        prom_printf("  ram_top      : %x\n", RELOC(ram_top));
+#ifdef CONFIG_KEXEC
+       if (RELOC(prom_crashk_base)) {
+               prom_printf("  crashk_base  : %x\n",  RELOC(prom_crashk_base));
+               prom_printf("  crashk_size  : %x\n", RELOC(prom_crashk_size));
+       }
+#endif
 }
 
 
@@ -2094,6 +2133,10 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4,
         */
        prom_init_mem();
 
+#ifdef CONFIG_KEXEC
+       if (RELOC(prom_crashk_base))
+               reserve_mem(RELOC(prom_crashk_base), RELOC(prom_crashk_size));
+#endif
        /*
         * Determine which cpu is actually running right _now_
         */
@@ -2150,6 +2193,16 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4,
        }
 #endif
 
+#ifdef CONFIG_KEXEC
+       if (RELOC(prom_crashk_base)) {
+               prom_setprop(_prom->chosen, "/chosen", "linux,crashkernel-base",
+                       PTRRELOC(&prom_crashk_base),
+                       sizeof(RELOC(prom_crashk_base)));
+               prom_setprop(_prom->chosen, "/chosen", "linux,crashkernel-size",
+                       PTRRELOC(&prom_crashk_size),
+                       sizeof(RELOC(prom_crashk_size)));
+       }
+#endif
        /*
         * Fixup any known bugs in the device-tree
         */