Patch set updated for coreboot: soc/intel/skylake: Use postcar functions for setting up new stack

[Rizwan Qureshi]

Rizwan Qureshi ([e-mail]) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/16332

-gerrit

commit d659e1b1a38339d973d7611c4fae064d6e4870ae
Author: Rizwan Qureshi 
Date:   Fri Aug 26 21:16:01 2016 +0530

soc/intel/skylake: Use postcar functions for setting up new stack

Setup stack and MTRRs using the postcar funtions provided
    in postcar_loader.c.

Change-Id: Ia5771e70386dbae9fa181e3635021dd187345123
    Signed-off-by: Rizwan Qureshi 
---
 src/soc/intel/skylake/romstage/romstage_fsp20.c | 52 +++++++++++++++++++++++--
 1 file changed, 49 insertions(+), 3 deletions(-)

diff --git a/src/soc/intel/skylake/romstage/romstage_fsp20.c b/src/soc/intel/skylake/romstage/romstage_fsp20.c
index 57b2a52..484c305 100644
--- a/src/soc/intel/skylake/romstage/romstage_fsp20.c
+++ b/src/soc/intel/skylake/romstage/romstage_fsp20.c
@@ -24,16 +24,24 @@
 #include <console/console.h>
 #include <device/pci_def.h>
 #include <fsp/util.h>
+#include <fsp/memmap.h>
 #include <soc/pci_devs.h>
 #include <soc/pm.h>
 #include <soc/romstage.h>
 #include <timestamp.h>
 #include <vboot/vboot_common.h>

+/*
+ * Romstage needs some stack for decompressing ramstage images, since the lzma
+ * lib keeps its state on the stack during romstage.
+ */
+#define ROMSTAGE_RAM_STACK_SIZE 0x5000
+
 asmlinkage void *car_stage_c_entry(void)
 {
    bool s3wake;
-	void *top_of_stack;
+	struct postcar_frame pcf;
+	uintptr_t top_of_ram;
    struct chipset_power_state *ps;

console_init();
@@ -46,8 +54,46 @@ asmlinkage void *car_stage_c_entry(void)
    s3wake = ps->prev_sleep_state == ACPI_S3;
    fsp_memory_init(s3wake);

-	top_of_stack = setup_stack_and_mtrrs();
-	return top_of_stack;
+	if (postcar_frame_init(&pcf, ROMSTAGE_RAM_STACK_SIZE))
+		die("Unable to initialize postcar frame.\n");
+
+	/*
+	 * We need to make sure ramstage will be run cached. At this
+	 * point exact location of ramstage in cbmem is not known.
+	 * Instruct postcar to cache 16 megs under cbmem top which is
+	 * a safe bet to cover ramstage.
+	 */
+	top_of_ram = (uintptr_t) cbmem_top();
+	printk(BIOS_DEBUG, "top_of_ram = 0x%lx\n", top_of_ram);
+	/* cbmem_top() needs to be at least 16 MiB aligned */
+	assert(ALIGN_DOWN(top_of_ram, 16*MiB) == top_of_ram);
+
+	postcar_frame_add_mtrr(&pcf, top_of_ram - 16*MiB, 16*MiB,
+				MTRR_TYPE_WRBACK);
+
+	if (IS_ENABLED(CONFIG_HAVE_SMI_HANDLER)) {
+		void *smm_base;
+		size_t smm_size;
+		uintptr_t tseg_base;
+
+		/*
+		 * Cache the TSEG region at the top of ram. This region is
+		 * not restricted to SMM mode until SMM has been relocated.
+		 * By setting the region to cacheable it provides faster access
+		 * when relocating the SMM handler as well as using the TSEG
+		 * region for other purposes.
+		 */
+		smm_region(&smm_base, &smm_size);
+		tseg_base = (uintptr_t)smm_base;
+		postcar_frame_add_mtrr(&pcf, tseg_base, smm_size,
+					MTRR_TYPE_WRBACK);
+	}
+
+	/* Cache the ROM as WP just below 4GiB. */
+	postcar_frame_add_mtrr(&pcf, 0xFFFFFFFF - CONFIG_ROM_SIZE + 1,
+				16*MiB, MTRR_TYPE_WRPROT);
+
+	return postcar_commit_mtrrs(&pcf);
 }

static void soc_memory_init_params(struct FSP_M_CONFIG *m_cfg)