From patchwork Mon May 25 01:48:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Glass X-Patchwork-Id: 246406 List-Id: U-Boot discussion From: sjg at chromium.org (Simon Glass) Date: Sun, 24 May 2020 19:48:38 -0600 Subject: [PATCH v2 01/26] x86: fsp: Reinit the FPU after FSP meminit In-Reply-To: <20200525014904.115621-1-sjg@chromium.org> References: <20200525014904.115621-1-sjg@chromium.org> Message-ID: <20200525014904.115621-2-sjg@chromium.org> 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 --- Changes in v2: None 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);