Kernel built with CONFIG_PPC_EARLY_DEBUG_OPAL enabled expects r8 & r9 to be filled with OPAL base & entry addresses respectively. Setting these registers allows the kernel to perform OPAL calls before the device tree is parsed.
Signed-off-by: Hari Bathini <hbath...@linux.ibm.com> --- v4 -> v5: * New patch. Updated opal_base & opal_entry values in r8 & r9 respectively. This change was part of the below dropped patch in v4: - https://lore.kernel.org/patchwork/patch/1275667/ arch/powerpc/kexec/file_load_64.c | 16 ++++++++++++++++ arch/powerpc/purgatory/trampoline_64.S | 15 +++++++++++++++ 2 files changed, 31 insertions(+) diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c index 8df085a22fd7..a5c1442590b2 100644 --- a/arch/powerpc/kexec/file_load_64.c +++ b/arch/powerpc/kexec/file_load_64.c @@ -713,6 +713,8 @@ int setup_purgatory_ppc64(struct kimage *image, const void *slave_code, const void *fdt, unsigned long kernel_load_addr, unsigned long fdt_load_addr) { + struct device_node *dn = NULL; + uint64_t val; int ret; ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr, @@ -735,9 +737,23 @@ int setup_purgatory_ppc64(struct kimage *image, const void *slave_code, goto out; } + /* Setup OPAL base & entry values */ + dn = of_find_node_by_path("/ibm,opal"); + if (dn) { + of_property_read_u64(dn, "opal-base-address", &val); + ret = kexec_purgatory_get_set_symbol(image, "opal_base", &val, + sizeof(val), false); + if (ret) + goto out; + + of_property_read_u64(dn, "opal-entry-address", &val); + ret = kexec_purgatory_get_set_symbol(image, "opal_entry", &val, + sizeof(val), false); + } out: if (ret) pr_err("Failed to setup purgatory symbols"); + of_node_put(dn); return ret; } diff --git a/arch/powerpc/purgatory/trampoline_64.S b/arch/powerpc/purgatory/trampoline_64.S index a5a83c3f53e6..464af8e8a4cb 100644 --- a/arch/powerpc/purgatory/trampoline_64.S +++ b/arch/powerpc/purgatory/trampoline_64.S @@ -61,6 +61,10 @@ master: li %r4,28 STWX_BE %r17,%r3,%r4 /* Store my cpu as __be32 at byte 28 */ 1: + /* Load opal base and entry values in r8 & r9 respectively */ + ld %r8,(opal_base - 0b)(%r18) + ld %r9,(opal_entry - 0b)(%r18) + /* load the kernel address */ ld %r4,(kernel - 0b)(%r18) @@ -102,6 +106,17 @@ dt_offset: .8byte 0x0 .size dt_offset, . - dt_offset + .balign 8 + .globl opal_base +opal_base: + .8byte 0x0 + .size opal_base, . - opal_base + + .balign 8 + .globl opal_entry +opal_entry: + .8byte 0x0 + .size opal_entry, . - opal_entry .data .balign 8 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec