[M] Change in coreboot[main]: soc/intel/pantherlake: Add soc_get_sku_power_limits() support

[Jérémy Compostella (Code Review)]

Jérémy Compostella has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/85443?usp=email )

Change subject: soc/intel/pantherlake: Add soc_get_sku_power_limits() support
......................................................................

soc/intel/pantherlake: Add soc_get_sku_power_limits() support

soc_get_sku_power_limits() implementation is required to use
variant_update_cpu_power_limits() which we would like to leverage for
Google fatcat missing battery use-case.

BUG=b:377798581
TEST=TBD

Change-Id: Ib89979e7933da62c8ddfec09ecf27f86b7ac0e09
Signed-off-by: Jeremy Compostella 
---
M src/soc/intel/pantherlake/systemagent.c
1 file changed, 38 insertions(+), 26 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/43/85443/1

diff --git a/src/soc/intel/pantherlake/systemagent.c b/src/soc/intel/pantherlake/systemagent.c
index e7a0701..1fa558a 100644
--- a/src/soc/intel/pantherlake/systemagent.c
+++ b/src/soc/intel/pantherlake/systemagent.c
@@ -137,25 +137,33 @@
    sa_add_fixed_mmio_resources(dev, resource_cnt, cfg_rsrc, count);
 }

-static void configure_tdp(struct device *dev)
+static u16 get_sa_pci_id(void)
 {
-	struct soc_power_limits_config *soc_config;
+	static u16 sa_pci_id;
    struct device *sa;
-	uint16_t sa_pci_id;
-	u8 tdp;
-	size_t i;
-	bool config_tdp = false;
+
+	if (sa_pci_id)
+		return sa_pci_id;
+
+	sa = pcidev_path_on_root(PCI_DEVFN_ROOT);
+	sa_pci_id = sa ? pci_read_config16(sa, PCI_DEVICE_ID) : 0xffff;
+
+	return sa_pci_id;
+}
+
+struct soc_power_limits_config *soc_get_sku_power_limits(void)
+{
    struct soc_intel_pantherlake_config *config;
+	u16 sa_pci_id;
+	u8 tdp;

config = config_of_soc();

/* Get System Agent PCI ID */
-	sa = pcidev_path_on_root(PCI_DEVFN_ROOT);
-	sa_pci_id = sa ? pci_read_config16(sa, PCI_DEVICE_ID) : 0xFFFF;
-
-	if (sa_pci_id == 0xFFFF) {
+	sa_pci_id = get_sa_pci_id();
+	if (sa_pci_id == 0xffff) {
    	printk(BIOS_WARNING, "Unknown SA PCI Device!\n");
-		return;
+		return NULL;
    }

tdp = get_cpu_tdp();
@@ -164,22 +172,26 @@
     * Choose power limits configuration based on the CPU SA PCI ID and
     * CPU TDP value.
     */
-	for (i = 0; i < ARRAY_SIZE(cpuid_to_ptl); i++) {
-		if (sa_pci_id == cpuid_to_ptl[i].cpu_id &&
-				tdp == cpuid_to_ptl[i].cpu_tdp) {
-			soc_config = &config->power_limits_config[cpuid_to_ptl[i].limits];
-			set_power_limits(MOBILE_SKU_PL1_TIME_SEC, soc_config);
-			config_tdp = true;
-			printk(BIOS_DEBUG, "Configured power limits for SA PCI ID: 0x%4x\n",
-				sa_pci_id);
-			break;
-		}
-	}
+	for (size_t i = 0; i < ARRAY_SIZE(cpuid_to_ptl); i++)
+		if (sa_pci_id == cpuid_to_ptl[i].cpu_id && tdp == cpuid_to_ptl[i].cpu_tdp)
+			return &config->power_limits_config[cpuid_to_ptl[i].limits];

-	if (!config_tdp) {
-		printk(BIOS_WARNING, "Skipped power limits configuration for SA PCI ID: 0x%4x\n",
-			sa_pci_id);
-		return;
+	return NULL;
+}
+
+static void configure_tdp(struct device *dev)
+{
+	struct soc_power_limits_config *power_limits;
+
+	power_limits = soc_get_sku_power_limits();
+	if (power_limits) {
+		set_power_limits(MOBILE_SKU_PL1_TIME_SEC, power_limits);
+		printk(BIOS_DEBUG, "Configured power limits for SA PCI ID: 0x%4x\n",
+		       get_sa_pci_id());
+	} else {
+		printk(BIOS_WARNING,
+		       "Skipped power limits configuration for SA PCI ID: 0x%4x\n",
+		       get_sa_pci_id());
    }
 }