From 3dada5a1a89f336f4b751548117949cf255cfcf6 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Thu, 2 Jul 2020 21:12:12 -0600 Subject: [PATCH] x86: fsp: Reinit the FPU after FSP meminit The APL FSP appears to leave the FPU in a bad state in that it has registers in use. This causes an error when the next FPU operation is performed. Work around this by re-resetting the FPU after calling FSP-M. This allows the freetype console to work correctly. Signed-off-by: Simon Glass Reviewed-by: Bin Meng --- arch/x86/cpu/i386/cpu.c | 5 +++++ arch/x86/include/asm/u-boot-x86.h | 8 ++++++++ arch/x86/lib/fsp2/fsp_meminit.c | 1 + 3 files changed, 14 insertions(+) diff --git a/arch/x86/cpu/i386/cpu.c b/arch/x86/cpu/i386/cpu.c index 435e50edad..d27324cb4e 100644 --- a/arch/x86/cpu/i386/cpu.c +++ b/arch/x86/cpu/i386/cpu.c @@ -363,6 +363,11 @@ static void setup_cpu_features(void) : : "i" (em_rst), "i" (mp_ne_set) : "eax"); } +void cpu_reinit_fpu(void) +{ + asm ("fninit\n"); +} + static void setup_identity(void) { /* identify CPU via cpuid and store the decoded info into gd->arch */ diff --git a/arch/x86/include/asm/u-boot-x86.h b/arch/x86/include/asm/u-boot-x86.h index 3e5d56d075..bd3f44014c 100644 --- a/arch/x86/include/asm/u-boot-x86.h +++ b/arch/x86/include/asm/u-boot-x86.h @@ -43,6 +43,14 @@ int x86_cpu_reinit_f(void); */ int x86_cpu_init_tpl(void); +/** + * cpu_reinit_fpu() - Reinit the FPU if something is wrong with it + * + * The FSP-M code can leave registers in use in the FPU. This functions reinits + * it so that the FPU can be used safely + */ +void cpu_reinit_fpu(void); + int cpu_init_f(void); void setup_gdt(struct global_data *id, u64 *gdt_addr); /* diff --git a/arch/x86/lib/fsp2/fsp_meminit.c b/arch/x86/lib/fsp2/fsp_meminit.c index 1a758147b0..faf9c29aef 100644 --- a/arch/x86/lib/fsp2/fsp_meminit.c +++ b/arch/x86/lib/fsp2/fsp_meminit.c @@ -85,6 +85,7 @@ int fsp_memory_init(bool s3wake, bool use_spi_flash) func = (fsp_memory_init_func)(hdr->img_base + hdr->fsp_mem_init); ret = func(&upd, &hob); bootstage_accum(BOOTSTAGE_ID_ACCUM_FSP_M); + cpu_reinit_fpu(); if (ret) return log_msg_ret("SDRAM init fail\n", ret);