1 files changed, 251 insertions, 0 deletions
diff --git a/src/soc/intel/alderlake/smmrelocate.c b/src/soc/intel/alderlake/smmrelocate.c
new file mode 100644
index 0000000000..17b4f2d713
--- /dev/null
+++ b/src/soc/intel/alderlake/smmrelocate.c
@@ -0,0 +1,251 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <console/console.h>
+#include <cpu/intel/common/common.h>
+#include <cpu/intel/em64t101_save_state.h>
+#include <cpu/intel/smm_reloc.h>
+#include <cpu/x86/mp.h>
+#include <cpu/x86/msr.h>
+#include <cpu/x86/mtrr.h>
+#include <cpu/x86/smm.h>
+#include <device/device.h>
+#include <device/pci.h>
+#include <device/pci_ops.h>
+#include <smp/node.h>
+#include <soc/cpu.h>
+#include <soc/msr.h>
+#include <soc/pci_devs.h>
+#include <soc/soc_chip.h>
+#include <string.h>
+#include <types.h>
+
+static void update_save_state(int cpu, uintptr_t curr_smbase,
+				uintptr_t staggered_smbase,
+				struct smm_relocation_params *relo_params)
+{
+	u32 smbase;
+	u32 iedbase;
+
+	/*
+	 * The relocated handler runs with all CPUs concurrently. Therefore
+	 * stagger the entry points adjusting SMBASE downwards by save state
+	 * size * CPU num.
+	 */
+	smbase = staggered_smbase;
+	iedbase = relo_params->ied_base;
+
+	printk(BIOS_DEBUG, "New SMBASE=0x%08x IEDBASE=0x%08x\n",
+	       smbase, iedbase);
+
+	/*
+	 * All threads need to set IEDBASE and SMBASE to the relocated
+	 * handler region. However, the save state location depends on the
+	 * smm_save_state_in_msrs field in the relocation parameters. If
+	 * smm_save_state_in_msrs is non-zero then the CPUs are relocating
+	 * the SMM handler in parallel, and each CPUs save state area is
+	 * located in their respective MSR space. If smm_save_state_in_msrs
+	 * is zero then the SMM relocation is happening serially so the
+	 * save state is at the same default location for all CPUs.
+	 */
+	if (relo_params->smm_save_state_in_msrs) {
+		msr_t smbase_msr;
+		msr_t iedbase_msr;
+
+		smbase_msr.lo = smbase;
+		smbase_msr.hi = 0;
+
+		/*
+		 * According the BWG the IEDBASE MSR is in bits 63:32. It's
+		 * not clear why it differs from the SMBASE MSR.
+		 */
+		iedbase_msr.lo = 0;
+		iedbase_msr.hi = iedbase;
+
+		wrmsr(SMBASE_MSR, smbase_msr);
+		wrmsr(IEDBASE_MSR, iedbase_msr);
+	} else {
+		em64t101_smm_state_save_area_t *save_state;
+
+		save_state = (void *)(curr_smbase + SMM_DEFAULT_SIZE -
+				      sizeof(*save_state));
+
+		save_state->smbase = smbase;
+		save_state->iedbase = iedbase;
+	}
+}
+
+/* Returns 1 if SMM MSR save state was set. */
+static int bsp_setup_msr_save_state(struct smm_relocation_params *relo_params)
+{
+	msr_t smm_mca_cap;
+
+	smm_mca_cap = rdmsr(SMM_MCA_CAP_MSR);
+	if (smm_mca_cap.hi & SMM_CPU_SVRSTR_MASK) {
+		msr_t smm_feature_control;
+
+		smm_feature_control = rdmsr(SMM_FEATURE_CONTROL_MSR);
+		smm_feature_control.hi = 0;
+		smm_feature_control.lo |= SMM_CPU_SAVE_EN;
+		wrmsr(SMM_FEATURE_CONTROL_MSR, smm_feature_control);
+		relo_params->smm_save_state_in_msrs = 1;
+	}
+	return relo_params->smm_save_state_in_msrs;
+}
+
+/*
+ * The relocation work is actually performed in SMM context, but the code
+ * resides in the ramstage module. This occurs by trampolining from the default
+ * SMRAM entry point to here.
+ */
+void smm_relocation_handler(int cpu, uintptr_t curr_smbase,
+				uintptr_t staggered_smbase)
+{
+	msr_t mtrr_cap;
+	struct smm_relocation_params *relo_params = &smm_reloc_params;
+
+	printk(BIOS_DEBUG, "In relocation handler: CPU %d\n", cpu);
+
+	/*
+	 * Determine if the processor supports saving state in MSRs. If so,
+	 * enable it before the non-BSPs run so that SMM relocation can occur
+	 * in parallel in the non-BSP CPUs.
+	 */
+	if (cpu == 0) {
+		/*
+		 * If smm_save_state_in_msrs is 1 then that means this is the
+		 * 2nd time through the relocation handler for the BSP.
+		 * Parallel SMM handler relocation is taking place. However,
+		 * it is desired to access other CPUs save state in the real
+		 * SMM handler. Therefore, disable the SMM save state in MSRs
+		 * feature.
+		 */
+		if (relo_params->smm_save_state_in_msrs) {
+			msr_t smm_feature_control;
+
+			smm_feature_control = rdmsr(SMM_FEATURE_CONTROL_MSR);
+			smm_feature_control.lo &= ~SMM_CPU_SAVE_EN;
+			wrmsr(SMM_FEATURE_CONTROL_MSR, smm_feature_control);
+		} else if (bsp_setup_msr_save_state(relo_params))
+			/*
+			 * Just return from relocation handler if MSR save
+			 * state is enabled. In that case the BSP will come
+			 * back into the relocation handler to setup the new
+			 * SMBASE as well disabling SMM save state in MSRs.
+			 */
+			return;
+	}
+
+	/* Make appropriate changes to the save state map. */
+	update_save_state(cpu, curr_smbase, staggered_smbase, relo_params);
+
+	/*
+	 * The SMRR MSRs are core-level registers, so if two threads that share
+	 * a core try to both set the lock bit (in the same physical register),
+	 * a #GP will be raised on the second write to that register (which is
+	 * exactly what the lock is supposed to do), therefore secondary threads
+	 * should exit here.
+	 */
+	if (intel_ht_sibling())
+		return;
+
+	/* Write SMRR MSRs based on indicated support. */
+	mtrr_cap = rdmsr(MTRR_CAP_MSR);
+
+	/* Set Lock bit if supported */
+	if (mtrr_cap.lo & SMRR_LOCK_SUPPORTED)
+		relo_params->smrr_mask.lo |= SMRR_PHYS_MASK_LOCK;
+
+	/* Write SMRRs if supported */
+	if (mtrr_cap.lo & SMRR_SUPPORTED)
+		write_smrr(relo_params);
+}
+
+static void fill_in_relocation_params(struct smm_relocation_params *params)
+{
+	uintptr_t tseg_base;
+	size_t tseg_size;
+	/* All range registers are aligned to 4KiB */
+	const u32 rmask = ~(4 * KiB - 1);
+
+	smm_region(&tseg_base, &tseg_size);
+
+	if (!IS_ALIGNED(tseg_base, tseg_size)) {
+		printk(BIOS_WARNING,
+		     "TSEG base not aligned with TSEG SIZE! Not setting SMRR\n");
+		return;
+	}
+
+	smm_subregion(SMM_SUBREGION_CHIPSET, &params->ied_base, &params->ied_size);
+
+	/* SMRR has 32-bits of valid address aligned to 4KiB. */
+	params->smrr_base.lo = (tseg_base & rmask) | MTRR_TYPE_WRBACK;
+	params->smrr_base.hi = 0;
+	params->smrr_mask.lo = (~(tseg_size - 1) & rmask) | MTRR_PHYS_MASK_VALID;
+	params->smrr_mask.hi = 0;
+}
+
+static void setup_ied_area(struct smm_relocation_params *params)
+{
+	char *ied_base;
+
+	struct ied_header ied = {
+		.signature = "INTEL RSVD",
+		.size = params->ied_size,
+		.reserved = {0},
+	};
+
+	ied_base = (void *)params->ied_base;
+
+	printk(BIOS_DEBUG, "IED base = 0x%08x\n", (u32)params->ied_base);
+	printk(BIOS_DEBUG, "IED size = 0x%08x\n", (u32)params->ied_size);
+
+	/* Place IED header at IEDBASE. */
+	memcpy(ied_base, &ied, sizeof(ied));
+
+	/* Zero out 32KiB at IEDBASE + 1MiB */
+	memset(ied_base + 1 * MiB, 0, 32 * KiB);
+}
+
+void smm_info(uintptr_t *perm_smbase, size_t *perm_smsize,
+				size_t *smm_save_state_size)
+{
+	printk(BIOS_DEBUG, "Setting up SMI for CPU\n");
+
+	fill_in_relocation_params(&smm_reloc_params);
+
+	smm_subregion(SMM_SUBREGION_HANDLER, perm_smbase, perm_smsize);
+
+	if (smm_reloc_params.ied_size)
+		setup_ied_area(&smm_reloc_params);
+
+	*smm_save_state_size = sizeof(em64t101_smm_state_save_area_t);
+}
+
+void smm_initialize(void)
+{
+	/* Clear the SMM state in the southbridge. */
+	smm_southbridge_clear_state();
+
+	/*
+	 * Run the relocation handler for on the BSP to check and set up
+	 * parallel SMM relocation.
+	 */
+	smm_initiate_relocation();
+
+	if (smm_reloc_params.smm_save_state_in_msrs)
+		printk(BIOS_DEBUG, "Doing parallel SMM relocation.\n");
+}
+
+void smm_relocate(void)
+{
+	/*
+	 * If smm_save_state_in_msrs is non-zero then parallel SMM relocation
+	 * shall take place. Run the relocation handler a second time on the
+	 * BSP to do * the final move. For APs, a relocation handler always
+	 * needs to be run.
+	 */
+	if (smm_reloc_params.smm_save_state_in_msrs)
+		smm_initiate_relocation_parallel();
+	else if (!boot_cpu())
+		smm_initiate_relocation();
+}