soc/intel/common/block/pcie/rtd3: Add PM methods to the device.

Add L23 enter/exit, modPHY power gate, and source clock control methods.
DL23: method for L2/L3 entry.
L23D: method for L2/L3 exit.
PSD0: method for modPHY power gate.
SRCK: method for enabling/disable source clock.
These optional methods are to be used in the device ACPI to construct
flows with root port's power management functions.

Test:
Enable and verify DL23, L23D, PSD0, SRCK methods in ssdt.

Signed-off-by: Cliff Huang <cliff.huang@intel.com>
Change-Id: I79de76f26c8424b036cb7d2719df68937599ca2f
Reviewed-on: https://review.coreboot.org/c/coreboot/+/61352
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

src/soc/intel/common/block/pcie/rtd3/chip.h

@@ -5,6 +5,17 @@
 
 #include <acpi/acpi_device.h>
 
+enum acpi_pcie_rp_pm_emit {
+	ACPI_PCIE_RP_EMIT_NONE      = 0x00,   /* None            */
+	ACPI_PCIE_RP_EMIT_L23       = 0x01,   /* L23             */
+	ACPI_PCIE_RP_EMIT_PSD0      = 0x02,   /* PSD0            */
+	ACPI_PCIE_RP_EMIT_SRCK      = 0x04,   /* SRCK            */
+	ACPI_PCIE_RP_EMIT_L23_PSD0  = 0x03,   /* L23, PSD0       */
+	ACPI_PCIE_RP_EMIT_L23_SRCK  = 0x05,   /* L23, SRCK       */
+	ACPI_PCIE_RP_EMIT_PSD0_SRCK = 0x06,   /* PSD0, SRCK      */
+	ACPI_PCIE_RP_EMIT_ALL       = 0x07    /* L23, PSD0, SRCK */
+};
+
 /* Device support at least one of enable/reset GPIO. */
 struct soc_intel_common_block_pcie_rtd3_config {
 	const char *desc;
@@ -45,6 +56,26 @@ struct soc_intel_common_block_pcie_rtd3_config {
 	 * Disable the ACPI-driven L23 Ready-to-Detect transition for the root port.
 	 */
 	bool disable_l23;
+
+	/*
+	 * Provides L23, modPHY gating, source clock enabling methods to the device
+	 * connected root port, mainly used in the device ACPI methods such as reset.
+	 * The methods to export are following this table:
+	 *-----------------------------------------------------------------------------------*
+	 | ext_pm_support | disable_l123 | srcclk_pin |   rp_type   |     exported methods   |
+	 *----------------+--------------+------------+-------------+------------------------*
+	 |     false      |       -      |     -      |      -      | None                   |
+	 |     true       |      true    |     =0     | PCIE_RP_CPU | None                   |
+	 |     true       |      true    |     =0     | PCIE_RP_PCH | SRCK                   |
+	 |     true       |      true    |     >0     | PCIE_RP_CPU | PSD0                   |
+	 |     true       |      true    |     >0     | PCIE_RP_PCH | PSD0, SRCK             |
+	 |     true       |      false   |     =0     | PCIE_RP_CPU | L23D, LD23             |
+	 |     true       |      false   |     =0     | PCIE_RP_PCH | L23D, LD23, SRCK       |
+	 |     true       |      false   |     >0     | PCIE_RP_CPU | L23D, LD23, PSD0       |
+	 |     true       |      false   |     >0     | PCIE_RP_PCH | L23D, LD23, PSD0, SRCK |
+	 *-----------------------------------------------------------------------------------*
+	 */
+	enum acpi_pcie_rp_pm_emit ext_pm_support;
 };
 
 #endif /* __SOC_INTEL_COMMON_BLOCK_PCIE_RTD3_CHIP_H__ */

src/soc/intel/common/block/pcie/rtd3/rtd3.c

@@ -100,6 +100,46 @@ static void pcie_rtd3_enable_modphy_pg(unsigned int pcie_rp, enum modphy_pg_stat
 	acpigen_emit_namestring(RTD3_MUTEX_PATH);
 }
 
+/* Method to enter L2/L3 */
+static void pcie_rtd3_acpi_method_dl23(void)
+{
+	acpigen_write_method_serialized("DL23", 0);
+	pcie_rtd3_acpi_l23_entry();
+	acpigen_pop_len(); /* Method */
+}
+
+/* Method to exit L2/L3 */
+static void pcie_rtd3_acpi_method_l23d(void)
+{
+	acpigen_write_method_serialized("L23D", 0);
+	pcie_rtd3_acpi_l23_exit();
+	acpigen_pop_len(); /* Method */
+}
+
+/* Method to disable PCH modPHY power gating */
+static void pcie_rtd3_acpi_method_pds0(unsigned int pcie_rp)
+{
+	acpigen_write_method_serialized("PSD0", 0);
+	pcie_rtd3_enable_modphy_pg(pcie_rp, PG_DISABLE);
+	acpigen_pop_len(); /* Method */
+}
+
+/* Method to enable/disable the source clock */
+static void pcie_rtd3_acpi_method_srck(unsigned int pcie_rp,
+	const struct soc_intel_common_block_pcie_rtd3_config *config)
+{
+	acpigen_write_method_serialized("SRCK", 1);
+
+	if (config->srcclk_pin >= 0) {
+		acpigen_write_if_lequal_op_op(ARG0_OP, 0);
+		pmc_ipc_acpi_set_pci_clock(pcie_rp, config->srcclk_pin, false);
+		acpigen_write_else();
+		pmc_ipc_acpi_set_pci_clock(pcie_rp, config->srcclk_pin, true);
+		acpigen_pop_len(); /* If */
+	}
+	acpigen_pop_len(); /* Method */
+}
+
 static void
 pcie_rtd3_acpi_method_on(unsigned int pcie_rp,
 			 const struct soc_intel_common_block_pcie_rtd3_config *config,
@@ -293,6 +333,24 @@ static void pcie_rtd3_acpi_fill_ssdt(const struct device *dev)
 		printk(BIOS_ERR, "%s: Unknown PCIe root port\n", __func__);
 		return;
 	}
+	if (config->disable_l23) {
+		if (config->ext_pm_support | ACPI_PCIE_RP_EMIT_L23) {
+			printk(BIOS_ERR, "%s: Can not export L23 methods\n", __func__);
+			return;
+		}
+	}
+	if (rp_type != PCIE_RP_PCH) {
+		if (config->ext_pm_support | ACPI_PCIE_RP_EMIT_PSD0) {
+			printk(BIOS_ERR, "%s: Can not export PSD0 method\n", __func__);
+			return;
+		}
+	}
+	if (config->srcclk_pin == 0) {
+		if (config->ext_pm_support | ACPI_PCIE_RP_EMIT_SRCK) {
+			printk(BIOS_ERR, "%s: Can not export SRCK method\n", __func__);
+			return;
+		}
+	}
 
 	printk(BIOS_INFO, "%s: Enable RTD3 for %s (%s)\n", scope, dev_path(parent),
 	       config->desc ?: dev->chip_ops->name);
@@ -316,10 +374,21 @@ static void pcie_rtd3_acpi_fill_ssdt(const struct device *dev)
 	acpigen_write_field("PXCS", fieldlist, ARRAY_SIZE(fieldlist),
 			    FIELD_ANYACC | FIELD_NOLOCK | FIELD_PRESERVE);
 
+	if (config->ext_pm_support | ACPI_PCIE_RP_EMIT_L23) {
+		pcie_rtd3_acpi_method_dl23();
+		pcie_rtd3_acpi_method_l23d();
+	}
+
 	/* Create the OpRegion to access the ModPHY PG registers (PCH RPs only) */
 	if (rp_type == PCIE_RP_PCH)
 		write_modphy_opregion(pcie_rp);
 
+	if (config->ext_pm_support | ACPI_PCIE_RP_EMIT_PSD0)
+		pcie_rtd3_acpi_method_pds0(pcie_rp);
+
+	if (config->ext_pm_support | ACPI_PCIE_RP_EMIT_SRCK)
+		pcie_rtd3_acpi_method_srck(pcie_rp, config);
+
 	/* ACPI Power Resource for controlling the attached device power. */
 	acpigen_write_power_res("RTD3", 0, 0, power_res_states, ARRAY_SIZE(power_res_states));
 	pcie_rtd3_acpi_method_status(config);