[PATCH v5 05/12] x86/resctrl: Detect and configure Slow Memory Bandwidth allocation

[Babu Moger <babu.moger@xxxxxxx>]

The QoS slow memory configuration details are available via
CPUID_Fn80000020_EDX_x02. Detect the available details and
initialize the rest to defaults.

Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
---
 arch/x86/kernel/cpu/resctrl/core.c        |   29 +++++++++++++++++++++++++++--
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |    2 +-
 arch/x86/kernel/cpu/resctrl/internal.h    |    1 +
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    |    8 +++++---
 4 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 53fbc3acad81..56c96607259c 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -227,9 +227,15 @@ static bool __rdt_get_mem_config_amd(struct rdt_resource *r)
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
 	union cpuid_0x10_3_eax eax;
 	union cpuid_0x10_x_edx edx;
-	u32 ebx, ecx;
+	u32 ebx, ecx, subleaf;
+
+	/*
+	 * Query CPUID_Fn80000020_EDX_x01 for MBA and
+	 * CPUID_Fn80000020_EDX_x02 for SMBA
+	 */
+	subleaf = (r->rid == RDT_RESOURCE_SMBA) ? 2 :  1;
 
-	cpuid_count(0x80000020, 1, &eax.full, &ebx, &ecx, &edx.full);
+	cpuid_count(0x80000020, subleaf, &eax.full, &ebx, &ecx, &edx.full);
 	hw_res->num_closid = edx.split.cos_max + 1;
 	r->default_ctrl = MAX_MBA_BW_AMD;
 
@@ -791,6 +797,19 @@ static __init bool get_mem_config(void)
 	return false;
 }
 
+static __init bool get_slow_mem_config(void)
+{
+	struct rdt_hw_resource *hw_res = &rdt_resources_all[RDT_RESOURCE_SMBA];
+
+	if (!rdt_cpu_has(X86_FEATURE_SMBA))
+		return false;
+
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+		return __rdt_get_mem_config_amd(&hw_res->r_resctrl);
+
+	return false;
+}
+
 static __init bool get_rdt_alloc_resources(void)
 {
 	struct rdt_resource *r;
@@ -821,6 +840,9 @@ static __init bool get_rdt_alloc_resources(void)
 	if (get_mem_config())
 		ret = true;
 
+	if (get_slow_mem_config())
+		ret = true;
+
 	return ret;
 }
 
@@ -910,6 +932,9 @@ static __init void rdt_init_res_defs_amd(void)
 		} else if (r->rid == RDT_RESOURCE_MBA) {
 			hw_res->msr_base = MSR_IA32_MBA_BW_BASE;
 			hw_res->msr_update = mba_wrmsr_amd;
+		} else if (r->rid == RDT_RESOURCE_SMBA) {
+			hw_res->msr_base = MSR_IA32_SMBA_BW_BASE;
+			hw_res->msr_update = mba_wrmsr_amd;
 		}
 	}
 }
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 7f38c8bd8429..480600b8e4cf 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -202,7 +202,7 @@ static int parse_line(char *line, struct resctrl_schema *s,
 	unsigned long dom_id;
 
 	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP &&
-	    r->rid == RDT_RESOURCE_MBA) {
+	    (r->rid == RDT_RESOURCE_MBA || r->rid == RDT_RESOURCE_SMBA)) {
 		rdt_last_cmd_puts("Cannot pseudo-lock MBA resource\n");
 		return -EINVAL;
 	}
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 24a1dfeb6cb2..c049a274383c 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -14,6 +14,7 @@
 #define MSR_IA32_L2_CBM_BASE		0xd10
 #define MSR_IA32_MBA_THRTL_BASE		0xd50
 #define MSR_IA32_MBA_BW_BASE		0xc0000200
+#define MSR_IA32_SMBA_BW_BASE		0xc0000280
 
 #define MSR_IA32_QM_CTR			0x0c8e
 #define MSR_IA32_QM_EVTSEL		0x0c8d
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index f276aff521e8..04b519bca50d 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1218,7 +1218,7 @@ static bool rdtgroup_mode_test_exclusive(struct rdtgroup *rdtgrp)
 
 	list_for_each_entry(s, &resctrl_schema_all, list) {
 		r = s->res;
-		if (r->rid == RDT_RESOURCE_MBA)
+		if (r->rid == RDT_RESOURCE_MBA || r->rid == RDT_RESOURCE_SMBA)
 			continue;
 		has_cache = true;
 		list_for_each_entry(d, &r->domains, list) {
@@ -1399,7 +1399,8 @@ static int rdtgroup_size_show(struct kernfs_open_file *of,
 				ctrl = resctrl_arch_get_config(r, d,
 							       rdtgrp->closid,
 							       schema->conf_type);
-				if (r->rid == RDT_RESOURCE_MBA)
+				if (r->rid == RDT_RESOURCE_MBA ||
+				    r->rid == RDT_RESOURCE_SMBA)
 					size = ctrl;
 				else
 					size = rdtgroup_cbm_to_size(r, d, ctrl);
@@ -2807,7 +2808,8 @@ static int rdtgroup_init_alloc(struct rdtgroup *rdtgrp)
 
 	list_for_each_entry(s, &resctrl_schema_all, list) {
 		r = s->res;
-		if (r->rid == RDT_RESOURCE_MBA) {
+		if (r->rid == RDT_RESOURCE_MBA ||
+		    r->rid == RDT_RESOURCE_SMBA) {
 			rdtgroup_init_mba(r);
 		} else {
 			ret = rdtgroup_init_cat(s, rdtgrp->closid);