drivers/intel/fsp2_0: Refactor MultiPhaseSiInit API calling method

FspMultiPhaseSiInit API was introduced with FSP 2.2 specification
onwards. EnableMultiPhaseSiliconInit is an arch UPD also introduced
as part of FSP 2.2 specification to allow calling FspMultiPhaseSiInit
API.

However, some platforms adhere to the FSP specification but
don't have arch UPD structure, for example : JSL, TGL and Xeon-SP.

Out of these platforms, TGL supports calling of FspMultiPhaseSiInit
API and considered EnableMultiPhaseSiliconInit as a platform-specific
UPD rather than an arch UPD to allow calling into FspMultiPhaseSiInit
API.

It is important to ensure that the UPD setting and the callback for
MultiPhaseInit are kept in sync, else it could result in broken
behavior e.g. a hang is seen in FSP if EnableMultiPhaseSiliconInit
UPD is set to 1 but the FspMultiPhaseSiInit API call is skipped.

This patch provides an option for users to choose to bypass calling
into MultiPhaseSiInit API and ensures the EnableMultiPhaseSiliconInit
UPD is set to its default state as `disable` so that FSP-S don't
consider MultiPhaseSiInit API is a mandatory entry point prior to
calling other FSP API entry points.

List of changes:
1. Add `FSPS_HAS_ARCH_UPD` Kconfig for SoC to select if
`FSPS_ARCH_UPD` structure is part of `FSPS_UPD` structure.
2. Drop `soc_fsp_multi_phase_init_is_enable()` from JSL and Xeon-SP
SoCs, a SoC override to callout that SoC doesn't support calling
MultiPhase Si Init is no longer required.
3. Add `FSPS_USE_MULTI_PHASE_INIT` Kconfig for SoC to specify if
SoC users want to enable `EnableMultiPhaseSiliconInit` arch UPD (using
`fsp_fill_common_arch_params()`) and execute FspMultiPhaseSiInit() API.
4. Presently selects `FSPS_USE_MULTI_PHASE_INIT` from IA TCSS common
code.
5. Add `fsp_is_multi_phase_init_enabled()` that check applicability of
MultiPhase Si Init prior calling FspMultiPhaseSiInit() API to
honor SoC users' decision.
6. Drop `arch_silicon_init_params()` from SoC as FSP driver (FSP 2.2)
would check the applicability of MultiPhase Si Init prior calling
FspMultiPhaseSiInit() API.

Additionally, selects FSPS_HAS_ARCH_UPD for Alder Lake as Alder Lake
FSPS_UPD structure has `FSPS_ARCH_UPD` structure and drops
`arch_silicon_init_params()` from SoC
`platform_fsp_silicon_init_params_cb()`.

Skip EnableMultiPhaseSiliconInit hardcoding for Tiger Lake and uses
the fsp_is_multi_phase_init_enabled() function to override
EnableMultiPhaseSiliconInit UPD prior calling MultiPhaseSiInit FSP API.

TEST=EnableMultiPhaseSiliconInit UPD is getting set or reset based on
SoC user selects FSPS_USE_MULTI_PHASE_INIT Kconfig.

Change-Id: I019fa8364605f5061d56e2d80b20e1a91857c423
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/56382
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

3 files changed, 36 insertions, 8 deletions

diff --git a/src/drivers/intel/fsp2_0/Kconfig b/src/drivers/intel/fsp2_0/Kconfig
index 3b03b6d1b7..ba93baa4de 100644
--- a/src/drivers/intel/fsp2_0/Kconfig
+++ b/src/drivers/intel/fsp2_0/Kconfig
@@ -274,4 +274,20 @@ config SOC_INTEL_COMMON_FSP_RESET
 	  Common code block to handle platform reset request raised by FSP. The FSP
 	  will use the FSP EAS v2.0 section 12.2.2 (OEM Status Code) to indicate that
 	  a reset is required.
+
+config FSPS_HAS_ARCH_UPD
+	bool
+	help
+	  SoC users must select this Kconfig if the `FSPS_UPD` header has architecture
+	  UPD structure as `FSPS_ARCH_UPD`. Typically, platform with FSP 2.2 specification
+	  onwards has support for `FSPS_ARCH_UPD` section as part of `FSPS_UPD` structure.
+	  But there are some exceptions as in TGL, JSL, XEON_SP FSP header doesn't have
+	  support for FSPS_ARCH_UPD.
+
+config FSPS_USE_MULTI_PHASE_INIT
+	bool
+	help
+	  SoC users to select this Kconfig to set EnableMultiPhaseSiliconInit to enable and
+	  execute FspMultiPhaseSiInit() API.
+
 endif
diff --git a/src/drivers/intel/fsp2_0/include/fsp/api.h b/src/drivers/intel/fsp2_0/include/fsp/api.h
index a095b78b5f..68b84703ca 100644
--- a/src/drivers/intel/fsp2_0/include/fsp/api.h
+++ b/src/drivers/intel/fsp2_0/include/fsp/api.h
@@ -47,8 +47,8 @@ void platform_fsp_memory_init_params_cb(FSPM_UPD *mupd, uint32_t version);
 void platform_fsp_silicon_init_params_cb(FSPS_UPD *supd);
 /* Callbacks for SoC/Mainboard specific overrides */
 void platform_fsp_multi_phase_init_cb(uint32_t phase_index);
-/* Check if SoC sets EnableMultiPhaseSiliconInit UPD */
-int soc_fsp_multi_phase_init_is_enable(void);
+/* Check if MultiPhase Si Init is enabled */
+bool fsp_is_multi_phase_init_enabled(void);
 /*
  * The following functions are used when FSP_PLATFORM_MEMORY_SETTINGS_VERSION
  * is employed allowing the mainboard and SoC to supply their own version
diff --git a/src/drivers/intel/fsp2_0/silicon_init.c b/src/drivers/intel/fsp2_0/silicon_init.c
index bf5230e90d..b3e60c25c3 100644
--- a/src/drivers/intel/fsp2_0/silicon_init.c
+++ b/src/drivers/intel/fsp2_0/silicon_init.c
@@ -29,11 +29,6 @@ void __weak platform_fsp_multi_phase_init_cb(uint32_t phase_index)
 	/* Leave for the SoC/Mainboard to implement if necessary. */
 }
 
-int __weak soc_fsp_multi_phase_init_is_enable(void)
-{
-	return 1;
-}
-
 /* FSP Specification < 2.2 has only 1 stage like FspSiliconInit. FSP specification >= 2.2
  * has multiple stages as below.
  */
@@ -77,6 +72,20 @@ static void fsps_return_value_handler(enum fsp_silicon_init_phases phases, uint3
 	}
 }
 
+bool fsp_is_multi_phase_init_enabled(void)
+{
+	return CONFIG(FSPS_USE_MULTI_PHASE_INIT) &&
+			 (fsps_hdr.multi_phase_si_init_entry_offset != 0);
+}
+
+static void fsp_fill_common_arch_params(FSPS_UPD *supd)
+{
+#if CONFIG(FSPS_HAS_ARCH_UPD)
+	FSPS_ARCH_UPD *s_arch_cfg = &supd->FspsArchUpd;
+	s_arch_cfg->EnableMultiPhaseSiliconInit = fsp_is_multi_phase_init_enabled();
+#endif
+}
+
 static void do_silicon_init(struct fsp_header *hdr)
 {
 	FSPS_UPD *upd, *supd;
@@ -106,6 +115,9 @@ static void do_silicon_init(struct fsp_header *hdr)
 
 	memcpy(upd, supd, hdr->cfg_region_size);
 
+	/* Fill common settings on behalf of chipset. */
+	if (CONFIG(FSPS_HAS_ARCH_UPD))
+		fsp_fill_common_arch_params(upd);
 	/* Give SoC/mainboard a chance to populate entries */
 	platform_fsp_silicon_init_params_cb(upd);
 
@@ -145,7 +157,7 @@ static void do_silicon_init(struct fsp_header *hdr)
 		return;
 
 	/* Check if SoC user would like to call Multi Phase Init */
-	if (!soc_fsp_multi_phase_init_is_enable())
+	if (!fsp_is_multi_phase_init_enabled())
 		return;
 
 	/* Call MultiPhaseSiInit */