cpu/x86/topology: Add node ID parser

Currently the SRAT table only exposes one proximity group as
it uses the LAPIC node_id, which is always initialized to 0.

Use CPUID leaf 0x1f or 0xb to gather the node ID and fill it
to make sure that at least one proximity group for every socket
is advertised.

For now the SNC config isn't taken into account.

Change-Id: Ia3ed1e5923aa18ca7619b32cde491fdb4da0fa0d
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/81515
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Shuo Liu <shuo.liu@intel.com>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>

3 files changed, 70 insertions, 0 deletions

diff --git a/src/cpu/x86/topology.c b/src/cpu/x86/topology.c
index 6c8d7fd420..baa4a7a584 100644
--- a/src/cpu/x86/topology.c
+++ b/src/cpu/x86/topology.c
@@ -4,6 +4,8 @@
 #include <device/device.h>
 #include <cpu/x86/topology.h>
 
+#define CPUID_EXTENDED_CPU_TOPOLOGY2 0x1f
+
 #define CPUID_EXTENDED_CPU_TOPOLOGY 0x0b
 #define LEVEL_TYPE_CORE 2
 #define LEVEL_TYPE_SMT 1
@@ -21,6 +23,64 @@
 #define CPUID_CPU_TOPOLOGY_CORE_BITS(res, threadbits) \
 	((CPUID_CPU_TOPOLOGY(LEVEL_BITS, (res).eax)) - threadbits)
 
+/* Return the level shift for the highest supported level (the package) */
+static enum cb_err get_cpu_package_bits(uint32_t *package_bits)
+{
+	struct cpuid_result cpuid_regs;
+	int level_num, cpu_id_op = 0;
+	const uint32_t cpuid_max_func = cpuid_get_max_func();
+
+	/*
+	 * Not all CPUs support this, those won't get topology filled in here.
+	 * CPU specific code can do this however.
+	 */
+	if (cpuid_max_func >= CPUID_EXTENDED_CPU_TOPOLOGY2)
+		cpu_id_op = CPUID_EXTENDED_CPU_TOPOLOGY2;
+	else if (cpuid_max_func >= CPUID_EXTENDED_CPU_TOPOLOGY)
+		cpu_id_op = CPUID_EXTENDED_CPU_TOPOLOGY;
+	else
+		return CB_ERR;
+
+	*package_bits = level_num = 0;
+	cpuid_regs = cpuid_ext(cpu_id_op, level_num);
+
+	/*
+	 * Sub-leaf index 0 enumerates SMT level, some AMD CPUs leave this CPUID leaf
+	 * reserved so bail out. Cpu specific code can fill in the topology later.
+	 */
+	if (CPUID_CPU_TOPOLOGY_LEVEL(cpuid_regs) != LEVEL_TYPE_SMT)
+		return CB_ERR;
+
+	do {
+		*package_bits = (CPUID_CPU_TOPOLOGY(LEVEL_BITS, (cpuid_regs).eax));
+		level_num++;
+		cpuid_regs = cpuid_ext(cpu_id_op, level_num);
+	/* Stop when level type is invalid i.e 0. */
+	} while (CPUID_CPU_TOPOLOGY_LEVEL(cpuid_regs));
+
+	return CB_SUCCESS;
+}
+
+void set_cpu_node_id_leaf_1f_b(struct device *cpu)
+{
+	static uint32_t package_bits;
+	static enum cb_err package_bits_ret;
+	static bool done = false;
+
+	if (!done) {
+		package_bits_ret = get_cpu_package_bits(&package_bits);
+		done = true;
+	}
+
+	const uint32_t apicid = cpu->path.apic.initial_lapicid;
+
+	/*
+	 *  If leaf_1f or leaf_b does not exist don't update the node_id.
+	 */
+	if (package_bits_ret == CB_SUCCESS)
+		cpu->path.apic.node_id = (apicid >> package_bits);
+}
+
 /* Get number of bits for core ID and SMT ID */
 static enum cb_err get_cpu_core_thread_bits(uint32_t *core_bits, uint32_t *thread_bits)
 {
diff --git a/src/include/cpu/x86/topology.h b/src/include/cpu/x86/topology.h
index db29d09f5b..d66f2eb821 100644
--- a/src/include/cpu/x86/topology.h
+++ b/src/include/cpu/x86/topology.h
@@ -11,4 +11,9 @@
  */
 void set_cpu_topology_from_leaf_b(struct device *cpu);
 
+/* Fill in the topology node ID in struct path APIC based CPUID EAX=0x1f
+ * or CPUID EAX=0xb. If those leaves aren't supported then the node ID
+ * won't be updated.
+ */
+void set_cpu_node_id_leaf_1f_b(struct device *cpu);
 #endif
diff --git a/src/soc/intel/xeon_sp/spr/cpu.c b/src/soc/intel/xeon_sp/spr/cpu.c
index 2ed8e2290a..f9c8e26273 100644
--- a/src/soc/intel/xeon_sp/spr/cpu.c
+++ b/src/soc/intel/xeon_sp/spr/cpu.c
@@ -14,6 +14,7 @@
 #include <cpu/x86/lapic.h>
 #include <cpu/x86/mp.h>
 #include <cpu/x86/mtrr.h>
+#include <cpu/x86/topology.h>
 #include <device/pci_mmio_cfg.h>
 #include <intelblocks/cpulib.h>
 #include <intelblocks/mp_init.h>
@@ -82,6 +83,10 @@ static void each_cpu_init(struct device *cpu)
 	       __func__, dev_path(cpu), cpu_index(), cpu->path.apic.apic_id,
 	       cpu->path.apic.package_id);
 
+	/* Populate the node ID. It will be used as proximity ID. */
+	set_cpu_node_id_leaf_1f_b(cpu);
+	assert (cpu->path.apic.node_id < CONFIG_MAX_SOCKET);
+
 	/*
 	 * Enable PWR_PERF_PLTFRM_OVR and PROCHOT_LOCK.
 	 * The value set by FSP is 20_005f, we set it to 1a_00a4_005b.