powercap: intel_rapl: Fix a sparse warning in TPMI interface

Depends on the interface used, the RAPL registers can be either MSR
indexes or memory mapped IO addresses. Current RAPL common code uses u64
to save both MSR and memory mapped IO registers. With this, when
handling register address with an __iomem annotation, it triggers a
sparse warning like below:

sparse warnings: (new ones prefixed by >>)
>> drivers/powercap/intel_rapl_tpmi.c:141:41: sparse: sparse: incorrect type in initializer (different address spaces) @@     expected unsigned long long [usertype] *tpmi_rapl_regs @@     got void [noderef] __iomem * @@
   drivers/powercap/intel_rapl_tpmi.c:141:41: sparse:     expected unsigned long long [usertype] *tpmi_rapl_regs
   drivers/powercap/intel_rapl_tpmi.c:141:41: sparse:     got void [noderef] __iomem *

Fix the problem by using a union to save the registers instead.
Suggested-by: David Laight <David.Laight@ACULAB.COM>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202307031405.dy3druuy-lkp@intel.com/Tested-by: Wang Wendy <wendy.wang@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/powercap/intel_rapl_common.c

@@ -818,7 +818,7 @@ static int rapl_read_data_raw(struct rapl_domain *rd,
 		return -EINVAL;
 
 	ra.reg = rd->regs[rpi->id];
-	if (!ra.reg)
+	if (!ra.reg.val)
 		return -EINVAL;
 
 	/* non-hardware data are collected by the polling thread */
@@ -830,7 +830,7 @@ static int rapl_read_data_raw(struct rapl_domain *rd,
 	ra.mask = rpi->mask;
 
 	if (rd->rp->priv->read_raw(get_rid(rd->rp), &ra)) {
-		pr_debug("failed to read reg 0x%llx for %s:%s\n", ra.reg, rd->rp->name, rd->name);
+		pr_debug("failed to read reg 0x%llx for %s:%s\n", ra.reg.val, rd->rp->name, rd->name);
 		return -EIO;
 	}
 
@@ -920,7 +920,7 @@ static int rapl_check_unit_core(struct rapl_domain *rd)
 	ra.mask = ~0;
 	if (rd->rp->priv->read_raw(get_rid(rd->rp), &ra)) {
 		pr_err("Failed to read power unit REG 0x%llx on %s:%s, exit.\n",
-			ra.reg, rd->rp->name, rd->name);
+			ra.reg.val, rd->rp->name, rd->name);
 		return -ENODEV;
 	}
 
@@ -948,7 +948,7 @@ static int rapl_check_unit_atom(struct rapl_domain *rd)
 	ra.mask = ~0;
 	if (rd->rp->priv->read_raw(get_rid(rd->rp), &ra)) {
 		pr_err("Failed to read power unit REG 0x%llx on %s:%s, exit.\n",
-			ra.reg, rd->rp->name, rd->name);
+			ra.reg.val, rd->rp->name, rd->name);
 		return -ENODEV;
 	}
 
@@ -1135,7 +1135,7 @@ static int rapl_check_unit_tpmi(struct rapl_domain *rd)
 	ra.mask = ~0;
 	if (rd->rp->priv->read_raw(get_rid(rd->rp), &ra)) {
 		pr_err("Failed to read power unit REG 0x%llx on %s:%s, exit.\n",
-			ra.reg, rd->rp->name, rd->name);
+			ra.reg.val, rd->rp->name, rd->name);
 		return -ENODEV;
 	}
 
@@ -1411,8 +1411,8 @@ static int rapl_get_domain_unit(struct rapl_domain *rd)
 	struct rapl_defaults *defaults = get_defaults(rd->rp);
 	int ret;
 
-	if (!rd->regs[RAPL_DOMAIN_REG_UNIT]) {
-		if (!rd->rp->priv->reg_unit) {
+	if (!rd->regs[RAPL_DOMAIN_REG_UNIT].val) {
+		if (!rd->rp->priv->reg_unit.val) {
 			pr_err("No valid Unit register found\n");
 			return -ENODEV;
 		}

drivers/powercap/intel_rapl_msr.c

@@ -34,28 +34,32 @@ static struct rapl_if_priv *rapl_msr_priv;
 
 static struct rapl_if_priv rapl_msr_priv_intel = {
 	.type = RAPL_IF_MSR,
-	.reg_unit = MSR_RAPL_POWER_UNIT,
-	.regs[RAPL_DOMAIN_PACKAGE] = {
-		MSR_PKG_POWER_LIMIT, MSR_PKG_ENERGY_STATUS, MSR_PKG_PERF_STATUS, 0, MSR_PKG_POWER_INFO },
-	.regs[RAPL_DOMAIN_PP0] = {
-		MSR_PP0_POWER_LIMIT, MSR_PP0_ENERGY_STATUS, 0, MSR_PP0_POLICY, 0 },
-	.regs[RAPL_DOMAIN_PP1] = {
-		MSR_PP1_POWER_LIMIT, MSR_PP1_ENERGY_STATUS, 0, MSR_PP1_POLICY, 0 },
-	.regs[RAPL_DOMAIN_DRAM] = {
-		MSR_DRAM_POWER_LIMIT, MSR_DRAM_ENERGY_STATUS, MSR_DRAM_PERF_STATUS, 0, MSR_DRAM_POWER_INFO },
-	.regs[RAPL_DOMAIN_PLATFORM] = {
-		MSR_PLATFORM_POWER_LIMIT, MSR_PLATFORM_ENERGY_STATUS, 0, 0, 0},
+	.reg_unit.msr = MSR_RAPL_POWER_UNIT,
+	.regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_LIMIT].msr	= MSR_PKG_POWER_LIMIT,
+	.regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_STATUS].msr	= MSR_PKG_ENERGY_STATUS,
+	.regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_PERF].msr	= MSR_PKG_PERF_STATUS,
+	.regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_INFO].msr	= MSR_PKG_POWER_INFO,
+	.regs[RAPL_DOMAIN_PP0][RAPL_DOMAIN_REG_LIMIT].msr	= MSR_PP0_POWER_LIMIT,
+	.regs[RAPL_DOMAIN_PP0][RAPL_DOMAIN_REG_STATUS].msr	= MSR_PP0_ENERGY_STATUS,
+	.regs[RAPL_DOMAIN_PP0][RAPL_DOMAIN_REG_POLICY].msr	= MSR_PP0_POLICY,
+	.regs[RAPL_DOMAIN_PP1][RAPL_DOMAIN_REG_LIMIT].msr	= MSR_PP1_POWER_LIMIT,
+	.regs[RAPL_DOMAIN_PP1][RAPL_DOMAIN_REG_STATUS].msr	= MSR_PP1_ENERGY_STATUS,
+	.regs[RAPL_DOMAIN_PP1][RAPL_DOMAIN_REG_POLICY].msr	= MSR_PP1_POLICY,
+	.regs[RAPL_DOMAIN_DRAM][RAPL_DOMAIN_REG_LIMIT].msr	= MSR_DRAM_POWER_LIMIT,
+	.regs[RAPL_DOMAIN_DRAM][RAPL_DOMAIN_REG_STATUS].msr	= MSR_DRAM_ENERGY_STATUS,
+	.regs[RAPL_DOMAIN_DRAM][RAPL_DOMAIN_REG_PERF].msr	= MSR_DRAM_PERF_STATUS,
+	.regs[RAPL_DOMAIN_DRAM][RAPL_DOMAIN_REG_INFO].msr	= MSR_DRAM_POWER_INFO,
+	.regs[RAPL_DOMAIN_PLATFORM][RAPL_DOMAIN_REG_LIMIT].msr	= MSR_PLATFORM_POWER_LIMIT,
+	.regs[RAPL_DOMAIN_PLATFORM][RAPL_DOMAIN_REG_STATUS].msr	= MSR_PLATFORM_ENERGY_STATUS,
 	.limits[RAPL_DOMAIN_PACKAGE] = BIT(POWER_LIMIT2),
 	.limits[RAPL_DOMAIN_PLATFORM] = BIT(POWER_LIMIT2),
 };
 
 static struct rapl_if_priv rapl_msr_priv_amd = {
 	.type = RAPL_IF_MSR,
-	.reg_unit = MSR_AMD_RAPL_POWER_UNIT,
-	.regs[RAPL_DOMAIN_PACKAGE] = {
-		0, MSR_AMD_PKG_ENERGY_STATUS, 0, 0, 0 },
-	.regs[RAPL_DOMAIN_PP0] = {
-		0, MSR_AMD_CORE_ENERGY_STATUS, 0, 0, 0 },
+	.reg_unit.msr = MSR_AMD_RAPL_POWER_UNIT,
+	.regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_STATUS].msr	= MSR_AMD_PKG_ENERGY_STATUS,
+	.regs[RAPL_DOMAIN_PP0][RAPL_DOMAIN_REG_STATUS].msr	= MSR_AMD_CORE_ENERGY_STATUS,
 };
 
 /* Handles CPU hotplug on multi-socket systems.
@@ -99,10 +103,8 @@ static int rapl_cpu_down_prep(unsigned int cpu)
 
 static int rapl_msr_read_raw(int cpu, struct reg_action *ra)
 {
-	u32 msr = (u32)ra->reg;
-
-	if (rdmsrl_safe_on_cpu(cpu, msr, &ra->value)) {
-		pr_debug("failed to read msr 0x%x on cpu %d\n", msr, cpu);
+	if (rdmsrl_safe_on_cpu(cpu, ra->reg.msr, &ra->value)) {
+		pr_debug("failed to read msr 0x%x on cpu %d\n", ra->reg.msr, cpu);
 		return -EIO;
 	}
 	ra->value &= ra->mask;
@@ -112,17 +114,16 @@ static int rapl_msr_read_raw(int cpu, struct reg_action *ra)
 static void rapl_msr_update_func(void *info)
 {
 	struct reg_action *ra = info;
-	u32 msr = (u32)ra->reg;
 	u64 val;
 
-	ra->err = rdmsrl_safe(msr, &val);
+	ra->err = rdmsrl_safe(ra->reg.msr, &val);
 	if (ra->err)
 		return;
 
 	val &= ~ra->mask;
 	val |= ra->value;
 
-	ra->err = wrmsrl_safe(msr, val);
+	ra->err = wrmsrl_safe(ra->reg.msr, val);
 }
 
 static int rapl_msr_write_raw(int cpu, struct reg_action *ra)
@@ -171,7 +172,7 @@ static int rapl_msr_probe(struct platform_device *pdev)
 
 	if (id) {
 		rapl_msr_priv->limits[RAPL_DOMAIN_PACKAGE] |= BIT(POWER_LIMIT4);
-		rapl_msr_priv->regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_PL4] =
+		rapl_msr_priv->regs[RAPL_DOMAIN_PACKAGE][RAPL_DOMAIN_REG_PL4].msr =
 			MSR_VR_CURRENT_CONFIG;
 		pr_info("PL4 support detected.\n");
 	}

drivers/powercap/intel_rapl_tpmi.c

@@ -59,10 +59,10 @@ static struct powercap_control_type *tpmi_control_type;
 
 static int tpmi_rapl_read_raw(int id, struct reg_action *ra)
 {
-	if (!ra->reg)
+	if (!ra->reg.mmio)
 		return -EINVAL;
 
-	ra->value = readq((void __iomem *)ra->reg);
+	ra->value = readq(ra->reg.mmio);
 
 	ra->value &= ra->mask;
 	return 0;
@@ -72,15 +72,15 @@ static int tpmi_rapl_write_raw(int id, struct reg_action *ra)
 {
 	u64 val;
 
-	if (!ra->reg)
+	if (!ra->reg.mmio)
 		return -EINVAL;
 
-	val = readq((void __iomem *)ra->reg);
+	val = readq(ra->reg.mmio);
 
 	val &= ~ra->mask;
 	val |= ra->value;
 
-	writeq(val, (void __iomem *)ra->reg);
+	writeq(val, ra->reg.mmio);
 	return 0;
 }
 
@@ -138,8 +138,7 @@ static int parse_one_domain(struct tpmi_rapl_package *trp, u32 offset)
 	enum tpmi_rapl_register reg_index;
 	enum rapl_domain_reg_id reg_id;
 	int tpmi_domain_size, tpmi_domain_flags;
-	u64 *tpmi_rapl_regs = trp->base + offset;
-	u64 tpmi_domain_header = readq((void __iomem *)tpmi_rapl_regs);
+	u64 tpmi_domain_header = readq(trp->base + offset);
 
 	/* Domain Parent bits are ignored for now */
 	tpmi_domain_version = tpmi_domain_header & 0xff;
@@ -180,7 +179,7 @@ static int parse_one_domain(struct tpmi_rapl_package *trp, u32 offset)
 		return -EINVAL;
 	}
 
-	if (trp->priv.regs[domain_type][RAPL_DOMAIN_REG_UNIT]) {
+	if (trp->priv.regs[domain_type][RAPL_DOMAIN_REG_UNIT].mmio) {
 		pr_warn(FW_BUG "Duplicate Domain type %d\n", tpmi_domain_type);
 		return -EINVAL;
 	}
@@ -218,7 +217,7 @@ static int parse_one_domain(struct tpmi_rapl_package *trp, u32 offset)
 		default:
 			continue;
 		}
-		trp->priv.regs[domain_type][reg_id] = (u64)&tpmi_rapl_regs[reg_index];
+		trp->priv.regs[domain_type][reg_id].mmio = trp->base + offset + reg_index * 8;
 	}
 
 	return 0;

drivers/thermal/intel/int340x_thermal/processor_thermal_rapl.c

@@ -57,10 +57,10 @@ static int rapl_mmio_cpu_down_prep(unsigned int cpu)
 
 static int rapl_mmio_read_raw(int cpu, struct reg_action *ra)
 {
-	if (!ra->reg)
+	if (!ra->reg.mmio)
 		return -EINVAL;
 
-	ra->value = readq((void __iomem *)ra->reg);
+	ra->value = readq(ra->reg.mmio);
 	ra->value &= ra->mask;
 	return 0;
 }
@@ -69,13 +69,13 @@ static int rapl_mmio_write_raw(int cpu, struct reg_action *ra)
 {
 	u64 val;
 
-	if (!ra->reg)
+	if (!ra->reg.mmio)
 		return -EINVAL;
 
-	val = readq((void __iomem *)ra->reg);
+	val = readq(ra->reg.mmio);
 	val &= ~ra->mask;
 	val |= ra->value;
-	writeq(val, (void __iomem *)ra->reg);
+	writeq(val, ra->reg.mmio);
 	return 0;
 }
 
@@ -92,13 +92,13 @@ int proc_thermal_rapl_add(struct pci_dev *pdev, struct proc_thermal_device *proc
 	for (domain = RAPL_DOMAIN_PACKAGE; domain < RAPL_DOMAIN_MAX; domain++) {
 		for (reg = RAPL_DOMAIN_REG_LIMIT; reg < RAPL_DOMAIN_REG_MAX; reg++)
 			if (rapl_regs->regs[domain][reg])
-				rapl_mmio_priv.regs[domain][reg] =
-						(u64)proc_priv->mmio_base +
+				rapl_mmio_priv.regs[domain][reg].mmio =
+						proc_priv->mmio_base +
 						rapl_regs->regs[domain][reg];
 		rapl_mmio_priv.limits[domain] = rapl_regs->limits[domain];
 	}
 	rapl_mmio_priv.type = RAPL_IF_MMIO;
-	rapl_mmio_priv.reg_unit = (u64)proc_priv->mmio_base + rapl_regs->reg_unit;
+	rapl_mmio_priv.reg_unit.mmio = proc_priv->mmio_base + rapl_regs->reg_unit;
 
 	rapl_mmio_priv.read_raw = rapl_mmio_read_raw;
 	rapl_mmio_priv.write_raw = rapl_mmio_write_raw;

include/linux/intel_rapl.h

@@ -100,10 +100,16 @@ struct rapl_package;
 
 #define RAPL_DOMAIN_NAME_LENGTH 16
 
+union rapl_reg {
+	void __iomem *mmio;
+	u32 msr;
+	u64 val;
+};
+
 struct rapl_domain {
 	char name[RAPL_DOMAIN_NAME_LENGTH];
 	enum rapl_domain_type id;
-	u64 regs[RAPL_DOMAIN_REG_MAX];
+	union rapl_reg regs[RAPL_DOMAIN_REG_MAX];
 	struct powercap_zone power_zone;
 	struct rapl_domain_data rdd;
 	struct rapl_power_limit rpl[NR_POWER_LIMITS];
@@ -116,7 +122,7 @@ struct rapl_domain {
 };
 
 struct reg_action {
-	u64 reg;
+	union rapl_reg reg;
 	u64 mask;
 	u64 value;
 	int err;
@@ -143,8 +149,8 @@ struct rapl_if_priv {
 	enum rapl_if_type type;
 	struct powercap_control_type *control_type;
 	enum cpuhp_state pcap_rapl_online;
-	u64 reg_unit;
-	u64 regs[RAPL_DOMAIN_MAX][RAPL_DOMAIN_REG_MAX];
+	union rapl_reg reg_unit;
+	union rapl_reg regs[RAPL_DOMAIN_MAX][RAPL_DOMAIN_REG_MAX];
 	int limits[RAPL_DOMAIN_MAX];
 	int (*read_raw)(int id, struct reg_action *ra);
 	int (*write_raw)(int id, struct reg_action *ra);