From ffaacd97fd37b9f4e825d8107f5cba5470458f0e Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Mon, 21 Jun 2021 16:49:38 +1000 Subject: [PATCH] powerpc/prom_init: Pass linux_banner to firmware via option vector 7 Pass the value of linux_banner to firmware via option vector 7. Option vector 7 is described in "LoPAR" Linux on Power Architecture Reference v2.9, in table B.7 on page 824: An ASCII character formatted null terminated string that describes the client operating system. The string shall be human readable and may be displayed on the console. The string can be up to 256 bytes total, including the nul terminator. linux_banner contains lots of information, and should make it possible to identify the exact kernel version that is running: const char linux_banner[] = "Linux version " UTS_RELEASE " (" LINUX_COMPILE_BY "@" LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION "\n"; For example: Linux version 4.15.0-144-generic (buildd@bos02-ppc64el-018) (gcc version 7.5.0 (Ubuntu 7.5.0-3ubuntu1~18.04)) #148-Ubuntu SMP Sat May 8 02:32:13 UTC 2021 (Ubuntu 4.15.0-144.148-generic 4.15.18) It's also printed at boot to the console/dmesg, which should make it possible to correlate what firmware receives with the console/dmesg on the machine. Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210621064938.2021419-2-mpe@ellerman.id.au --- arch/powerpc/kernel/prom_init.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c index c18d55f8b951..cb5be081e499 100644 --- a/arch/powerpc/kernel/prom_init.c +++ b/arch/powerpc/kernel/prom_init.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include #include @@ -944,6 +945,10 @@ struct option_vector6 { u8 os_name; } __packed; +struct option_vector7 { + u8 os_id[256]; +} __packed; + struct ibm_arch_vec { struct { u32 mask, val; } pvrs[14]; @@ -966,6 +971,9 @@ struct ibm_arch_vec { u8 vec6_len; struct option_vector6 vec6; + + u8 vec7_len; + struct option_vector7 vec7; } __packed; static const struct ibm_arch_vec ibm_architecture_vec_template __initconst = { @@ -1112,6 +1120,9 @@ static const struct ibm_arch_vec ibm_architecture_vec_template __initconst = { .secondary_pteg = 0, .os_name = OV6_LINUX, }, + + /* option vector 7: OS Identification */ + .vec7_len = VECTOR_LENGTH(sizeof(struct option_vector7)), }; static struct ibm_arch_vec __prombss ibm_architecture_vec ____cacheline_aligned; @@ -1340,6 +1351,8 @@ static void __init prom_check_platform_support(void) memcpy(&ibm_architecture_vec, &ibm_architecture_vec_template, sizeof(ibm_architecture_vec)); + prom_strscpy_pad(ibm_architecture_vec.vec7.os_id, linux_banner, 256); + if (prop_len > 1) { int i; u8 vec[8]; -- 2.11.0