drivers/intel/fsp2_0: Refactor for earlier graphics memory WC MTRR

Moves the MTRR setup for graphics memory (GMADR) from the
`soc_load_logo_by_coreboot()` function to `do_silicon_init()`. This
refactors the logic into a new helper function,
`soc_mark_gfx_memory()`, which acquires a temporary Write-Combine
(WC) MTRR.

The MTRR is now configured earlier in the silicon initialization
process, making the setup and cleanup independent of the
`soc_load_logo_by_coreboot()` function itself.

This improves FSP-S performance and ensures the MTRR is correctly
managed within the silicon initialization flow which was earlier
missed when platform selects `USE_COREBOOT_FOR_BMP_RENDERING` aka
rendering the BMP logo using coreboot driver and not using FSP driver
logic.

The cleanup of the MTRR is also moved to `do_silicon_init()` to pair
with the earlier setup.

TEST=Successfully boot to OS on google/fatcat using coreboot for logo
rendering.

w/o this patch

```
    963:returning from FspMultiPhaseSiInit    1,164,839 (123,244)
```

w/ this patch

```
    963:returning from FspMultiPhaseSiInit    1,143,974 (115,443)
```

Change-Id: I5da3178c622f5fd6cb3d7f3f574e59f9ed5a5b3d
Signed-off-by: Subrata Banik <subratabanik@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/88982
Reviewed-by: Jérémy Compostella <jeremy.compostella@intel.com>
Reviewed-by: Pranava Y N <pranavayn@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/drivers/intel/fsp2_0/cb_logo.c

@@ -39,11 +39,29 @@ static void program_igd_lmembar(uint32_t base)
 	pci_or_config16(SA_DEV_IGD, PCI_COMMAND, enable_mask);
 }
 
+/*
+ * Marks the GMADR range as Write-Combine (WC) memory.
+ *
+ * This function acquires and configures a temporary MTRR for the GMADR range.
+ *
+ * @return valid MTRR index on success, -1 on failure.
+ */
+int soc_mark_gfx_memory(void)
+{
+	/* Set up a temporary Write Combine (WC) MTRR for the GMADR range */
+	int temp_mtrr_index = acquire_and_configure_mtrr(GMADR_BASE, GMADR_SIZE, MTRR_TYPE_WRCOMB);
+	if (temp_mtrr_index < 0) {
+		printk(BIOS_ERR, "Failed to configure WC MTRR for GMADR.\n");
+		return -1;
+	}
+
+	return temp_mtrr_index;
+}
+
 void soc_load_logo_by_coreboot(void)
 {
 	const struct hob_graphics_info *ginfo;
 	struct soc_intel_common_config *config = chip_get_common_soc_structure();
-	int temp_mtrr_index = -1;
 	struct logo_config logo_cfg;
 	size_t size;
 
@@ -57,13 +75,6 @@ void soc_load_logo_by_coreboot(void)
 	/* Program the IGD LMEMBAR */
 	program_igd_lmembar(GMADR_BASE);
 
-	/* Set up a temporary Write Combine (WC) MTRR for the GMADR range */
-	temp_mtrr_index = acquire_and_configure_mtrr(GMADR_BASE, GMADR_SIZE, MTRR_TYPE_WRCOMB);
-	if (temp_mtrr_index < 0) {
-		printk(BIOS_ERR, "Failed to configure WC MTRR for GMADR.\n");
-		return;
-	}
-
 	/*
 	 * Adjusts panel orientation for external display when the lid is closed.
 	 *
@@ -88,7 +99,4 @@ void soc_load_logo_by_coreboot(void)
 	logo_cfg.logo_bottom_margin = config->logo_bottom_margin;
 
 	render_logo_to_framebuffer(&logo_cfg);
-
-	/* Clear temporary Write Combine (WC) MTRR */
-	clear_var_mtrr(temp_mtrr_index);
 }

src/drivers/intel/fsp2_0/include/fsp/api.h

@@ -108,8 +108,10 @@ void soc_load_logo_by_fsp(FSPS_UPD *supd);
  */
 #if CONFIG(USE_COREBOOT_FOR_BMP_RENDERING)
 void soc_load_logo_by_coreboot(void);
+int soc_mark_gfx_memory(void);
 #else
 static inline void soc_load_logo_by_coreboot(void) { /* nop */ }
+static inline int soc_mark_gfx_memory(void) { return -1; }
 #endif
 
 /* Update the SOC specific memory config param for mma. */

src/drivers/intel/fsp2_0/silicon_init.c

@@ -6,6 +6,7 @@
 #include <cbfs.h>
 #include <cbmem.h>
 #include <commonlib/fsp.h>
+#include <cpu/x86/mtrr.h>
 #include <stdlib.h>
 #include <console/console.h>
 #include <fsp/api.h>
@@ -96,6 +97,7 @@ static void do_silicon_init(struct fsp_header *hdr)
 	fsp_multi_phase_init_fn multi_phase_si_init;
 	struct fsp_multi_phase_params multi_phase_params;
 	struct fsp_multi_phase_get_number_of_phases_params multi_phase_get_number;
+	int temp_mtrr_index = -1;
 
 	supd = (FSPS_UPD *)(uintptr_t)(hdr->cfg_region_offset + hdr->image_base);
 
@@ -123,6 +125,9 @@ static void do_silicon_init(struct fsp_header *hdr)
 	/* Give SoC/mainboard a chance to populate entries */
 	platform_fsp_silicon_init_params_cb(upd);
 
+	if (CONFIG(BMP_LOGO) && CONFIG(USE_COREBOOT_FOR_BMP_RENDERING))
+		temp_mtrr_index = soc_mark_gfx_memory();
+
 	/*
 	 * Populate UPD entries for the logo if the platform utilizes
 	 * the FSP's capability for rendering bitmap (BMP) images.
@@ -229,6 +234,10 @@ static void do_silicon_init(struct fsp_header *hdr)
 		 * the rendering.
 		 */
 		timestamp_add_now(TS_FIRMWARE_SPLASH_RENDERED);
+
+		/* Clear temporary Write Combine (WC) MTRR */
+		if (temp_mtrr_index >= 0)
+			clear_var_mtrr(temp_mtrr_index);
 	}
 
 	/* Reinitialize CPUs if FSP-S has done MP Init */