acpigen,soc/amd,cpu/intel: rework static DWORD for CPPC table

Some elements in the ACPI CPPC table allow static DWORDs. Instead of
using a fake register resource, use a tagged union with the two types
"register" and "DWORD" and respective macros for CPPC table entries.

Test: dumped SSDT before and after do not differ.

Change-Id: Ib853261b5c0ea87ae2424fed188f2d1872be9a06
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57886
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>

6 files changed, 73 insertions, 67 deletions

diff --git a/src/acpi/acpigen.c b/src/acpi/acpigen.c
index e0892e654f94..37bfec165432 100644
--- a/src/acpi/acpigen.c
+++ b/src/acpi/acpigen.c
@@ -1798,13 +1798,11 @@ void acpigen_write_CPPC_package(const struct cppc_config *config)
 	acpigen_write_byte(config->version);
 
 	for (i = 0; i < max; ++i) {
-		const acpi_addr_t *reg = &(config->regs[i]);
-		if (reg->space_id == ACPI_ADDRESS_SPACE_MEMORY &&
-		    reg->bit_width == 32 && reg->access_size == ACPI_ACCESS_SIZE_UNDEFINED) {
-			acpigen_write_dword(reg->addrl);
-		} else {
-			acpigen_write_register_resource(reg);
-		}
+		const cppc_entry_t *entry = &config->entries[i];
+		if (entry->type == CPPC_TYPE_DWORD)
+			acpigen_write_dword(entry->dword);
+		else
+			acpigen_write_register_resource(&entry->reg);
 	}
 	acpigen_pop_len();
 }
diff --git a/src/cpu/intel/common/common.h b/src/cpu/intel/common/common.h
index fdacd1f74bc1..909f75ac4097 100644
--- a/src/cpu/intel/common/common.h
+++ b/src/cpu/intel/common/common.h
@@ -4,6 +4,7 @@
 #define _CPU_INTEL_COMMON_H
 
 #include <types.h>
+#include <acpi/acpigen.h>
 
 void set_vmx_and_lock(void);
 void set_feature_ctrl_vmx(void);
diff --git a/src/cpu/intel/common/common_init.c b/src/cpu/intel/common/common_init.c
index 6203922fd829..765a174dd12f 100644
--- a/src/cpu/intel/common/common_init.c
+++ b/src/cpu/intel/common/common_init.c
@@ -105,42 +105,35 @@ void cpu_init_cppc_config(struct cppc_config *config, u32 version)
 {
 	config->version = version;
 
-	config->regs[CPPC_HIGHEST_PERF]			= ACPI_REG_MSR(IA32_HWP_CAPABILITIES, 0, 8);
-	config->regs[CPPC_NOMINAL_PERF]			= ACPI_REG_MSR(MSR_PLATFORM_INFO, 8, 8);
-	config->regs[CPPC_LOWEST_NONL_PERF]		= ACPI_REG_MSR(IA32_HWP_CAPABILITIES, 16, 8);
-	config->regs[CPPC_LOWEST_PERF]			= ACPI_REG_MSR(IA32_HWP_CAPABILITIES, 24, 8);
-	config->regs[CPPC_GUARANTEED_PERF]		= ACPI_REG_MSR(IA32_HWP_CAPABILITIES, 8, 8);
-	config->regs[CPPC_DESIRED_PERF]			= ACPI_REG_MSR(IA32_HWP_REQUEST, 16, 8);
-	config->regs[CPPC_MIN_PERF]			= ACPI_REG_MSR(IA32_HWP_REQUEST, 0, 8);
-	config->regs[CPPC_MAX_PERF]			= ACPI_REG_MSR(IA32_HWP_REQUEST, 8, 8);
-	config->regs[CPPC_PERF_REDUCE_TOLERANCE]	= ACPI_REG_UNSUPPORTED;
-	config->regs[CPPC_TIME_WINDOW]			= ACPI_REG_UNSUPPORTED;
-	config->regs[CPPC_COUNTER_WRAP]			= ACPI_REG_UNSUPPORTED;
-	config->regs[CPPC_REF_PERF_COUNTER]		= ACPI_REG_MSR(IA32_MPERF, 0, 64);
-	config->regs[CPPC_DELIVERED_PERF_COUNTER]	= ACPI_REG_MSR(IA32_APERF, 0, 64);
-	config->regs[CPPC_PERF_LIMITED]			= ACPI_REG_MSR(IA32_HWP_STATUS, 2, 1);
-	config->regs[CPPC_ENABLE]			= ACPI_REG_MSR(IA32_PM_ENABLE, 0, 1);
+	config->entries[CPPC_HIGHEST_PERF]		= CPPC_REG_MSR(IA32_HWP_CAPABILITIES, 0, 8);
+	config->entries[CPPC_NOMINAL_PERF]		= CPPC_REG_MSR(MSR_PLATFORM_INFO, 8, 8);
+	config->entries[CPPC_LOWEST_NONL_PERF]		= CPPC_REG_MSR(IA32_HWP_CAPABILITIES, 16, 8);
+	config->entries[CPPC_LOWEST_PERF]		= CPPC_REG_MSR(IA32_HWP_CAPABILITIES, 24, 8);
+	config->entries[CPPC_GUARANTEED_PERF]		= CPPC_REG_MSR(IA32_HWP_CAPABILITIES, 8, 8);
+	config->entries[CPPC_DESIRED_PERF]		= CPPC_REG_MSR(IA32_HWP_REQUEST, 16, 8);
+	config->entries[CPPC_MIN_PERF]			= CPPC_REG_MSR(IA32_HWP_REQUEST, 0, 8);
+	config->entries[CPPC_MAX_PERF]			= CPPC_REG_MSR(IA32_HWP_REQUEST, 8, 8);
+	config->entries[CPPC_PERF_REDUCE_TOLERANCE]	= CPPC_UNSUPPORTED;
+	config->entries[CPPC_TIME_WINDOW]		= CPPC_UNSUPPORTED;
+	config->entries[CPPC_COUNTER_WRAP]		= CPPC_UNSUPPORTED;
+	config->entries[CPPC_REF_PERF_COUNTER]		= CPPC_REG_MSR(IA32_MPERF, 0, 64);
+	config->entries[CPPC_DELIVERED_PERF_COUNTER]	= CPPC_REG_MSR(IA32_APERF, 0, 64);
+	config->entries[CPPC_PERF_LIMITED]		= CPPC_REG_MSR(IA32_HWP_STATUS, 2, 1);
+	config->entries[CPPC_ENABLE]			= CPPC_REG_MSR(IA32_PM_ENABLE, 0, 1);
 
 	if (version < 2)
 		return;
 
-	config->regs[CPPC_AUTO_SELECT] = (acpi_addr_t){
-		.space_id    = ACPI_ADDRESS_SPACE_MEMORY,
-		.bit_width   = 32,
-		.bit_offset  = 0,
-		.access_size = ACPI_ACCESS_SIZE_UNDEFINED,
-		.addrl       = 1,
-	};
-
-	config->regs[CPPC_AUTO_ACTIVITY_WINDOW]		= ACPI_REG_MSR(IA32_HWP_REQUEST, 32, 10);
-	config->regs[CPPC_PERF_PREF]			= ACPI_REG_MSR(IA32_HWP_REQUEST, 24, 8);
-	config->regs[CPPC_REF_PERF]			= ACPI_REG_UNSUPPORTED;
+	config->entries[CPPC_AUTO_SELECT]		= CPPC_DWORD(1);
+	config->entries[CPPC_AUTO_ACTIVITY_WINDOW]	= CPPC_REG_MSR(IA32_HWP_REQUEST, 32, 10);
+	config->entries[CPPC_PERF_PREF]			= CPPC_REG_MSR(IA32_HWP_REQUEST, 24, 8);
+	config->entries[CPPC_REF_PERF]			= CPPC_UNSUPPORTED;
 
 	if (version < 3)
 		return;
 
-	config->regs[CPPC_LOWEST_FREQ]			= ACPI_REG_UNSUPPORTED;
-	config->regs[CPPC_NOMINAL_FREQ]			= ACPI_REG_UNSUPPORTED;
+	config->entries[CPPC_LOWEST_FREQ]		= CPPC_UNSUPPORTED;
+	config->entries[CPPC_NOMINAL_FREQ]		= CPPC_UNSUPPORTED;
 }
 
 void set_aesni_lock(void)
diff --git a/src/include/acpi/acpigen.h b/src/include/acpi/acpigen.h
index 3af0959cfd48..463c16d2b261 100644
--- a/src/include/acpi/acpigen.h
+++ b/src/include/acpi/acpigen.h
@@ -265,24 +265,37 @@ enum cppc_fields {
 	CPPC_MAX_FIELDS_VER_3,
 };
 
+typedef struct cppc_entry {
+	enum { CPPC_TYPE_REG, CPPC_TYPE_DWORD } type;
+	union {
+		acpi_addr_t reg;
+		uint32_t dword;
+	};
+} cppc_entry_t;
+
+#define CPPC_DWORD(_dword) \
+	(cppc_entry_t){ \
+		.type  = CPPC_TYPE_DWORD, \
+		.dword = _dword, \
+	}
+
+#define CPPC_REG(_reg) \
+	(cppc_entry_t){ \
+		.type = CPPC_TYPE_REG, \
+		.reg  = _reg, \
+	}
+
+#define CPPC_REG_MSR(address, offset, width) CPPC_REG(ACPI_REG_MSR(address, offset, width))
+#define CPPC_UNSUPPORTED CPPC_REG(ACPI_REG_UNSUPPORTED)
+
 struct cppc_config {
 	u32 version; /* must be 1, 2, or 3 */
 	/*
 	 * The generic acpi_addr_t structure is being used, though
 	 * anything besides PPC or FFIXED generally requires checking
 	 * if the OS has advertised support for it (via _OSC).
-	 *
-	 * NOTE: some fields permit DWORDs to be used.  If you
-	 * provide a System Memory register with all zeros (which
-	 * represents unsupported) then this will be used as-is.
-	 * Otherwise, a System Memory register with a 32-bit
-	 * width will be converted into a DWORD field (the value
-	 * of which will be the value of 'addrl'.  Any other use
-	 * of System Memory register is currently undefined.
-	 * (i.e., if you have an actual need for System Memory
-	 * then you'll need to adjust this kludge).
 	 */
-	acpi_addr_t regs[CPPC_MAX_FIELDS_VER_3];
+	cppc_entry_t entries[CPPC_MAX_FIELDS_VER_3];
 };
 
 void acpigen_write_return_integer(uint64_t arg);
diff --git a/src/soc/amd/cezanne/cppc.c b/src/soc/amd/cezanne/cppc.c
index 9d681c6ba74b..1afa26f3e1e9 100644
--- a/src/soc/amd/cezanne/cppc.c
+++ b/src/soc/amd/cezanne/cppc.c
@@ -15,35 +15,35 @@ void cpu_init_cppc_config(struct cppc_config *config, u32 version)
 {
 	config->version = version;
 
-	config->regs[CPPC_HIGHEST_PERF]			= ACPI_REG_MSR(MSR_CPPC_CAPABILITY_1, SHIFT_CPPC_CAPABILITY_1_HIGHEST_PERF, 8);
-	config->regs[CPPC_NOMINAL_PERF]			= ACPI_REG_MSR(MSR_CPPC_CAPABILITY_1, SHIFT_CPPC_CAPABILITY_1_NOMINAL_PERF, 8);
-	config->regs[CPPC_LOWEST_NONL_PERF]		= ACPI_REG_MSR(MSR_CPPC_CAPABILITY_1, SHIFT_CPPC_CAPABILITY_1_LOW_NON_LIN_PERF, 8);
-	config->regs[CPPC_LOWEST_PERF]			= ACPI_REG_MSR(MSR_CPPC_CAPABILITY_1, SHIFT_CPPC_CAPABILITY_1_LOWEST_PERF, 8);
-	config->regs[CPPC_GUARANTEED_PERF]		= ACPI_REG_UNSUPPORTED;
-	config->regs[CPPC_DESIRED_PERF]			= ACPI_REG_MSR(MSR_CPPC_REQUEST, SHIFT_CPPC_REQUEST_DES_PERF, 8);
-	config->regs[CPPC_MIN_PERF]			= ACPI_REG_MSR(MSR_CPPC_REQUEST, SHIFT_CPPC_REQUEST_MIN_PERF, 8);
-	config->regs[CPPC_MAX_PERF]			= ACPI_REG_MSR(MSR_CPPC_REQUEST, SHIFT_CPPC_REQUEST_MAX_PERF, 8);
-	config->regs[CPPC_PERF_REDUCE_TOLERANCE]	= ACPI_REG_UNSUPPORTED;
-	config->regs[CPPC_TIME_WINDOW]			= ACPI_REG_UNSUPPORTED;
-	config->regs[CPPC_COUNTER_WRAP]			= ACPI_REG_UNSUPPORTED;
-	config->regs[CPPC_REF_PERF_COUNTER]		= ACPI_REG_MSR(MSR_MAX_PERFORMANCE_FREQUENCY_CLOCK_COUNT, 0, 64);
-	config->regs[CPPC_DELIVERED_PERF_COUNTER]	= ACPI_REG_MSR(MSR_ACTUAL_PERFORMANCE_FREQUENCY_CLOCK_COUNT, 0, 64);
-	config->regs[CPPC_PERF_LIMITED]			= ACPI_REG_MSR(MSR_CPPC_STATUS, 1, 1);
-	config->regs[CPPC_ENABLE]			= ACPI_REG_MSR(MSR_CPPC_ENABLE, 0, 1);
+	config->entries[CPPC_HIGHEST_PERF]		= CPPC_REG_MSR(MSR_CPPC_CAPABILITY_1, SHIFT_CPPC_CAPABILITY_1_HIGHEST_PERF, 8);
+	config->entries[CPPC_NOMINAL_PERF]		= CPPC_REG_MSR(MSR_CPPC_CAPABILITY_1, SHIFT_CPPC_CAPABILITY_1_NOMINAL_PERF, 8);
+	config->entries[CPPC_LOWEST_NONL_PERF]		= CPPC_REG_MSR(MSR_CPPC_CAPABILITY_1, SHIFT_CPPC_CAPABILITY_1_LOW_NON_LIN_PERF, 8);
+	config->entries[CPPC_LOWEST_PERF]		= CPPC_REG_MSR(MSR_CPPC_CAPABILITY_1, SHIFT_CPPC_CAPABILITY_1_LOWEST_PERF, 8);
+	config->entries[CPPC_GUARANTEED_PERF]		= CPPC_UNSUPPORTED;
+	config->entries[CPPC_DESIRED_PERF]		= CPPC_REG_MSR(MSR_CPPC_REQUEST, SHIFT_CPPC_REQUEST_DES_PERF, 8);
+	config->entries[CPPC_MIN_PERF]			= CPPC_REG_MSR(MSR_CPPC_REQUEST, SHIFT_CPPC_REQUEST_MIN_PERF, 8);
+	config->entries[CPPC_MAX_PERF]			= CPPC_REG_MSR(MSR_CPPC_REQUEST, SHIFT_CPPC_REQUEST_MAX_PERF, 8);
+	config->entries[CPPC_PERF_REDUCE_TOLERANCE]	= CPPC_UNSUPPORTED;
+	config->entries[CPPC_TIME_WINDOW]		= CPPC_UNSUPPORTED;
+	config->entries[CPPC_COUNTER_WRAP]		= CPPC_UNSUPPORTED;
+	config->entries[CPPC_REF_PERF_COUNTER]		= CPPC_REG_MSR(MSR_MAX_PERFORMANCE_FREQUENCY_CLOCK_COUNT, 0, 64);
+	config->entries[CPPC_DELIVERED_PERF_COUNTER]	= CPPC_REG_MSR(MSR_ACTUAL_PERFORMANCE_FREQUENCY_CLOCK_COUNT, 0, 64);
+	config->entries[CPPC_PERF_LIMITED]		= CPPC_REG_MSR(MSR_CPPC_STATUS, 1, 1);
+	config->entries[CPPC_ENABLE]			= CPPC_REG_MSR(MSR_CPPC_ENABLE, 0, 1);
 
 	if (version < 2)
 		return;
 
-	config->regs[CPPC_AUTO_SELECT]			= ACPI_REG_UNSUPPORTED;
-	config->regs[CPPC_AUTO_ACTIVITY_WINDOW]		= ACPI_REG_UNSUPPORTED;
-	config->regs[CPPC_PERF_PREF]			= ACPI_REG_MSR(MSR_CPPC_REQUEST, SHIFT_CPPC_REQUEST_ENERGY_PERF_PREF, 8);
-	config->regs[CPPC_REF_PERF]			= ACPI_REG_UNSUPPORTED;
+	config->entries[CPPC_AUTO_SELECT]		= CPPC_UNSUPPORTED;
+	config->entries[CPPC_AUTO_ACTIVITY_WINDOW]	= CPPC_UNSUPPORTED;
+	config->entries[CPPC_PERF_PREF]			= CPPC_REG_MSR(MSR_CPPC_REQUEST, SHIFT_CPPC_REQUEST_ENERGY_PERF_PREF, 8);
+	config->entries[CPPC_REF_PERF]			= CPPC_UNSUPPORTED;
 
 	if (version < 3)
 		return;
 
-	config->regs[CPPC_LOWEST_FREQ]			= ACPI_REG_UNSUPPORTED;
-	config->regs[CPPC_NOMINAL_FREQ]			= ACPI_REG_UNSUPPORTED;
+	config->entries[CPPC_LOWEST_FREQ]		= CPPC_UNSUPPORTED;
+	config->entries[CPPC_NOMINAL_FREQ]		= CPPC_UNSUPPORTED;
 }
 
 
diff --git a/src/soc/amd/cezanne/include/soc/cppc.h b/src/soc/amd/cezanne/include/soc/cppc.h
index 60a5efd33417..e2f4daaf4976 100644
--- a/src/soc/amd/cezanne/include/soc/cppc.h
+++ b/src/soc/amd/cezanne/include/soc/cppc.h
@@ -4,6 +4,7 @@
 #define _CPU_AMD_COMMON_H
 
 #include <types.h>
+#include <acpi/acpigen.h>
 
 struct cppc_config;
 void cpu_init_cppc_config(struct cppc_config *config, u32 version);