acpi/acpigen: Constify CST functions' pointers

The `acpigen_write_CST_package` and `acpigen_write_CST_package_entry`
functions don't modify the provided C-state information. So, make the
pointer parameters read-only to enforce this. Also constify arguments
where possible.

Change-Id: I9e18d82ee6c16e4435b8fad6d467e58c33194cf4
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/58391
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>

src/acpi/acpigen.c

@@ -994,7 +994,7 @@ void acpigen_write_PSD_package(u32 domain, u32 numprocs, PSD_coord coordtype)
 	acpigen_pop_len();
 }
 
-void acpigen_write_CST_package_entry(acpi_cstate_t *cstate)
+void acpigen_write_CST_package_entry(const acpi_cstate_t *cstate)
 {
 	acpigen_write_package(4);
 	acpigen_write_register_resource(&cstate->resource);
@@ -1004,7 +1004,7 @@ void acpigen_write_CST_package_entry(acpi_cstate_t *cstate)
 	acpigen_pop_len();
 }
 
-void acpigen_write_CST_package(acpi_cstate_t *cstate, int nentries)
+void acpigen_write_CST_package(const acpi_cstate_t *cstate, int nentries)
 {
 	int i;
 	acpigen_write_name("_CST");

src/include/acpi/acpigen.h

@@ -357,8 +357,8 @@ void acpigen_write_PSS_package(u32 coreFreq, u32 power, u32 transLat,
 void acpigen_write_pss_object(const struct acpi_sw_pstate *pstate_values, size_t nentries);
 typedef enum { SW_ALL = 0xfc, SW_ANY = 0xfd, HW_ALL = 0xfe } PSD_coord;
 void acpigen_write_PSD_package(u32 domain, u32 numprocs, PSD_coord coordtype);
-void acpigen_write_CST_package_entry(acpi_cstate_t *cstate);
-void acpigen_write_CST_package(acpi_cstate_t *entry, int nentries);
+void acpigen_write_CST_package_entry(const acpi_cstate_t *cstate);
+void acpigen_write_CST_package(const acpi_cstate_t *entry, int nentries);
 typedef enum { CSD_HW_ALL = 0xfe } CSD_coord;
 void acpigen_write_CSD_package(u32 domain, u32 numprocs, CSD_coord coordtype,
 				u32 index);

src/soc/amd/cezanne/acpi.c

@@ -279,7 +279,7 @@ void generate_cpu_entries(const struct device *device)
 		.addrl = PS_STS_REG,
 	};
 
-	acpi_cstate_t cstate_info[] = {
+	const acpi_cstate_t cstate_info[] = {
 		[0] = {
 			.ctype = 1,
 			.latency = 1,

src/soc/amd/picasso/acpi.c

@@ -289,7 +289,7 @@ void generate_cpu_entries(const struct device *device)
 		.addrl = PS_STS_REG,
 	};
 
-	acpi_cstate_t cstate_info[] = {
+	const acpi_cstate_t cstate_info[] = {
 		[0] = {
 			.ctype = 1,
 			.latency = 1,

src/soc/intel/baytrail/acpi.c

@@ -28,7 +28,7 @@
 	}
 
 /* C-state map without S0ix */
-static acpi_cstate_t cstate_map[] = {
+static const acpi_cstate_t cstate_map[] = {
 	{
 		/* C1 */
 		.ctype = 1, /* ACPI C1 */

src/soc/intel/braswell/acpi.c

@@ -36,7 +36,7 @@
 	}
 
 /* C-state map without S0ix */
-static acpi_cstate_t cstate_map[] = {
+static const acpi_cstate_t cstate_map[] = {
 	{
 		/* C1 */
 		.ctype = 1, /* ACPI C1 */