soc/amd/cezanne,picasso: factor out common early non-car cache setup

This implementation is the same for all SoC that select
SOC_AMD_COMMON_BLOCK_NONCAR, so factor it out to the common AMD non-CAR
CPU support code folder.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I53528f0bb75e9d945740ad5065c75e7de7b5878f
Reviewed-on: https://review.coreboot.org/c/coreboot/+/61257
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

3 files changed, 83 insertions, 0 deletions

diff --git a/src/soc/amd/common/block/cpu/noncar/Makefile.inc b/src/soc/amd/common/block/cpu/noncar/Makefile.inc
index 808679dfea..532bb32918 100644
--- a/src/soc/amd/common/block/cpu/noncar/Makefile.inc
+++ b/src/soc/amd/common/block/cpu/noncar/Makefile.inc
@@ -1,5 +1,6 @@
 ifeq ($(CONFIG_SOC_AMD_COMMON_BLOCK_NONCAR),y)
 
+bootblock-y += early_cache.c
 bootblock-y += pre_c.S
 bootblock-y += write_resume_eip.c
 romstage-y += memmap.c
diff --git a/src/soc/amd/common/block/cpu/noncar/early_cache.c b/src/soc/amd/common/block/cpu/noncar/early_cache.c
new file mode 100644
index 0000000000..b9650a96a7
--- /dev/null
+++ b/src/soc/amd/common/block/cpu/noncar/early_cache.c
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <amdblocks/cpu.h>
+#include <cpu/amd/mtrr.h>
+#include <cpu/x86/cache.h>
+#include <cpu/x86/msr.h>
+#include <cpu/x86/mtrr.h>
+#include <soc/iomap.h>
+
+/*
+ * PSP performs the memory training and setting up DRAM map prior to x86 cores being released.
+ * Honor TOP_MEM and set up caching from 0 til TOP_MEM. Likewise, route lower memory addresses
+ * covered by fixed MTRRs to DRAM except for 0xa0000-0xc0000.
+ */
+void early_cache_setup(void)
+{
+	msr_t top_mem;
+	msr_t sys_cfg;
+	msr_t mtrr_def_type;
+	msr_t fixed_mtrr_ram;
+	msr_t fixed_mtrr_mmio;
+	struct var_mtrr_context mtrr_ctx;
+
+	var_mtrr_context_init(&mtrr_ctx, NULL);
+	top_mem = rdmsr(TOP_MEM);
+	/* Enable RdDram and WrDram attributes in fixed MTRRs. */
+	sys_cfg = rdmsr(SYSCFG_MSR);
+	sys_cfg.lo |= SYSCFG_MSR_MtrrFixDramModEn;
+
+	/* Fixed MTRR constants. */
+	fixed_mtrr_ram.lo = fixed_mtrr_ram.hi =
+		((MTRR_TYPE_WRBACK | MTRR_READ_MEM | MTRR_WRITE_MEM) <<  0) |
+		((MTRR_TYPE_WRBACK | MTRR_READ_MEM | MTRR_WRITE_MEM) <<  8) |
+		((MTRR_TYPE_WRBACK | MTRR_READ_MEM | MTRR_WRITE_MEM) << 16) |
+		((MTRR_TYPE_WRBACK | MTRR_READ_MEM | MTRR_WRITE_MEM) << 24);
+	fixed_mtrr_mmio.lo = fixed_mtrr_mmio.hi =
+		((MTRR_TYPE_UNCACHEABLE) <<  0) |
+		((MTRR_TYPE_UNCACHEABLE) <<  8) |
+		((MTRR_TYPE_UNCACHEABLE) << 16) |
+		((MTRR_TYPE_UNCACHEABLE) << 24);
+
+	/* Prep default MTRR type. */
+	mtrr_def_type = rdmsr(MTRR_DEF_TYPE_MSR);
+	mtrr_def_type.lo &= ~MTRR_DEF_TYPE_MASK;
+	mtrr_def_type.lo |= MTRR_TYPE_UNCACHEABLE;
+	mtrr_def_type.lo |= MTRR_DEF_TYPE_EN | MTRR_DEF_TYPE_FIX_EN;
+
+	disable_cache();
+
+	wrmsr(SYSCFG_MSR, sys_cfg);
+
+	clear_all_var_mtrr();
+
+	var_mtrr_set(&mtrr_ctx, 0, ALIGN_DOWN(top_mem.lo, 8*MiB), MTRR_TYPE_WRBACK);
+	/* TODO: check if we should always mark 16 MByte below 4 GByte as WRPROT */
+	var_mtrr_set(&mtrr_ctx, FLASH_BASE_ADDR, CONFIG_ROM_SIZE, MTRR_TYPE_WRPROT);
+
+	/* Set up RAM caching for everything below 1MiB except for 0xa0000-0xc0000 . */
+	wrmsr(MTRR_FIX_64K_00000, fixed_mtrr_ram);
+	wrmsr(MTRR_FIX_16K_80000, fixed_mtrr_ram);
+	wrmsr(MTRR_FIX_16K_A0000, fixed_mtrr_mmio);
+	wrmsr(MTRR_FIX_4K_C0000, fixed_mtrr_ram);
+	wrmsr(MTRR_FIX_4K_C8000, fixed_mtrr_ram);
+	wrmsr(MTRR_FIX_4K_D0000, fixed_mtrr_ram);
+	wrmsr(MTRR_FIX_4K_D8000, fixed_mtrr_ram);
+	wrmsr(MTRR_FIX_4K_E0000, fixed_mtrr_ram);
+	wrmsr(MTRR_FIX_4K_E8000, fixed_mtrr_ram);
+	wrmsr(MTRR_FIX_4K_F0000, fixed_mtrr_ram);
+	wrmsr(MTRR_FIX_4K_F8000, fixed_mtrr_ram);
+
+	wrmsr(MTRR_DEF_TYPE_MSR, mtrr_def_type);
+
+	/* Enable Fixed and Variable MTRRs. */
+	sys_cfg.lo |= SYSCFG_MSR_MtrrFixDramEn | SYSCFG_MSR_MtrrVarDramEn;
+	sys_cfg.lo |= SYSCFG_MSR_TOM2En | SYSCFG_MSR_TOM2WB;
+	/* AGESA currently expects SYSCFG_MSR_MtrrFixDramModEn to be set. Once
+	   MP init happens in coreboot proper it can be knocked down. */
+	wrmsr(SYSCFG_MSR, sys_cfg);
+
+	enable_cache();
+}
diff --git a/src/soc/amd/common/block/include/amdblocks/cpu.h b/src/soc/amd/common/block/include/amdblocks/cpu.h
index 0627bc1377..6576c3b993 100644
--- a/src/soc/amd/common/block/include/amdblocks/cpu.h
+++ b/src/soc/amd/common/block/include/amdblocks/cpu.h
@@ -3,6 +3,7 @@
 #ifndef AMD_BLOCK_CPU_H
 #define AMD_BLOCK_CPU_H
 
+void early_cache_setup(void);
 int get_cpu_count(void);
 void set_cstate_io_addr(void);
 void write_resume_eip(void);