drivers/espi: ite: Add it51xxx compatibility with it8xxx2 support retained

The driver originally supported only it8xxx2 series. This updates
introduces compatibility allow it to also support it51xxx series
with minimal changes.

Signed-off-by: Tim Lin <tim2.lin@ite.corp-partner.google.com>

Author: GTLin08

drivers/espi/Kconfig.it8xxx2

@@ -5,7 +5,7 @@ config ESPI_IT8XXX2
 	bool "ITE IT8XXX2 embedded controller ESPI driver"
 	default y
 	depends on DT_HAS_ITE_IT8XXX2_ESPI_ENABLED
-	depends on SOC_IT8XXX2
+	depends on SOC_IT8XXX2 || SOC_IT51XXX
 	help
 	  Enable ITE IT8XXX2 ESPI driver.
 

drivers/espi/espi_it8xxx2.c

@@ -9,6 +9,7 @@
 #include <assert.h>
 #include <zephyr/drivers/espi.h>
 #include <zephyr/drivers/gpio.h>
+#include <zephyr/drivers/interrupt_controller/wuc_ite_it51xxx.h>
 #include <zephyr/drivers/interrupt_controller/wuc_ite_it8xxx2.h>
 #include <zephyr/kernel.h>
 #include <zephyr/sys/util.h>
@@ -21,8 +22,7 @@
 #include <zephyr/irq.h>
 LOG_MODULE_REGISTER(espi, CONFIG_ESPI_LOG_LEVEL);
 
-#define ESPI_IT8XXX2_GET_GCTRL_BASE \
-	((struct gctrl_it8xxx2_regs *)DT_REG_ADDR(DT_NODELABEL(gctrl)))
+#define ESPI_ITE_GET_GCTRL_BASE ((struct gctrl_ite_ec_regs *)DT_REG_ADDR(DT_NODELABEL(gctrl)))
 
 #define IT8XXX2_ESPI_IRQ     DT_INST_IRQ_BY_IDX(0, 0, irq)
 #define IT8XXX2_ESPI_VW_IRQ  DT_INST_IRQ_BY_IDX(0, 1, irq)
@@ -827,9 +827,10 @@ static const struct ec2i_t smfi_settings[] = {
 static void smfi_it8xxx2_init(const struct device *dev)
 {
 	const struct espi_it8xxx2_config *const config = dev->config;
-	struct smfi_it8xxx2_regs *const smfi_reg =
-		(struct smfi_it8xxx2_regs *)config->base_smfi;
-	struct gctrl_it8xxx2_regs *const gctrl = ESPI_IT8XXX2_GET_GCTRL_BASE;
+	struct smfi_ite_ec_regs *const smfi_reg = (struct smfi_ite_ec_regs *)config->base_smfi;
+
+#ifdef CONFIG_SOC_SERIES_IT8XXX2
+	struct gctrl_ite_ec_regs *const gctrl = ESPI_ITE_GET_GCTRL_BASE;
 	uint8_t h2ram_offset;
 
 	/* Set the host to RAM cycle address offset */
@@ -838,6 +839,7 @@ static void smfi_it8xxx2_init(const struct device *dev)
 	gctrl->GCTRL_H2ROFSR =
 		(gctrl->GCTRL_H2ROFSR & ~IT8XXX2_ESPI_H2RAM_OFFSET_MASK) |
 		h2ram_offset;
+#endif
 
 #ifdef CONFIG_ESPI_PERIPHERAL_EC_HOST_CMD
 	memset(&h2ram_pool[CONFIG_ESPI_PERIPHERAL_HOST_CMD_PARAM_PORT_NUM], 0,
@@ -929,12 +931,13 @@ static void pnpcfg_it8xxx2_configure(const struct device *dev,
 
 #define PNPCFG(_s)						\
 	pnpcfg_it8xxx2_configure(dev, _s##_settings, ARRAY_SIZE(_s##_settings))
+extern uint8_t _h2ram_pool_start[];
 
 static void pnpcfg_it8xxx2_init(const struct device *dev)
 {
 	const struct espi_it8xxx2_config *const config = dev->config;
 	struct ec2i_regs *const ec2i = (struct ec2i_regs *)config->base_ec2i;
-	struct gctrl_it8xxx2_regs *const gctrl = ESPI_IT8XXX2_GET_GCTRL_BASE;
+	struct gctrl_ite_ec_regs *const gctrl = ESPI_ITE_GET_GCTRL_BASE;
 
 	/* The register pair to access PNPCFG is 004Eh and 004Fh */
 	gctrl->GCTRL_BADRSEL = 0x1;
@@ -953,6 +956,15 @@ static void pnpcfg_it8xxx2_init(const struct device *dev)
 #if defined(CONFIG_ESPI_PERIPHERAL_EC_HOST_CMD) || \
 	defined(CONFIG_ESPI_PERIPHERAL_ACPI_SHM_REGION)
 	PNPCFG(smfi);
+
+#ifdef CONFIG_SOC_SERIES_IT51XXX
+	uint8_t h2ram_pool_idx;
+
+	h2ram_pool_idx = ((uint32_t)_h2ram_pool_start & IT8XXX2_ESPI_H2RAM_BASEADDR_MASK) /
+			 IT8XXX2_ESPI_H2RAM_POOL_SIZE_MAX;
+	/* H2RAM 4K page select */
+	ec2i_it8xxx2_write(dev, HOST_INDEX_DSLDC13, h2ram_pool_idx);
+#endif
 #endif
 }
 
@@ -1086,7 +1098,7 @@ static void pmc1_it8xxx2_init(const struct device *dev)
 static void port80_it8xxx2_isr(const struct device *dev)
 {
 	struct espi_it8xxx2_data *const data = dev->data;
-	struct gctrl_it8xxx2_regs *const gctrl = ESPI_IT8XXX2_GET_GCTRL_BASE;
+	struct gctrl_ite_ec_regs *const gctrl = ESPI_ITE_GET_GCTRL_BASE;
 	struct espi_event evt = {
 		ESPI_BUS_PERIPHERAL_NOTIFICATION,
 		(ESPI_PERIPHERAL_INDEX_0 << 16) | ESPI_PERIPHERAL_DEBUG_PORT80,
@@ -1107,7 +1119,7 @@ static void port80_it8xxx2_isr(const struct device *dev)
 static void port80_it8xxx2_init(const struct device *dev)
 {
 	ARG_UNUSED(dev);
-	struct gctrl_it8xxx2_regs *const gctrl = ESPI_IT8XXX2_GET_GCTRL_BASE;
+	struct gctrl_ite_ec_regs *const gctrl = ESPI_ITE_GET_GCTRL_BASE;
 
 	/* Accept Port 80h (and 81h) Cycle */
 	if (IS_ENABLED(CONFIG_ESPI_IT8XXX2_PORT_81_CYCLE)) {
@@ -2395,7 +2407,11 @@ void espi_it8xxx2_enable_trans_irq(const struct device *dev, bool enable)
 	} else {
 		irq_disable(IT8XXX2_TRANS_IRQ);
 		/* Clear pending interrupt */
+#ifdef CONFIG_SOC_SERIES_IT51XXX
+		it51xxx_wuc_clear_status(config->wuc.wucs, config->wuc.mask);
+#else
 		it8xxx2_wuc_clear_status(config->wuc.wucs, config->wuc.mask);
+#endif
 	}
 }
 
@@ -2431,7 +2447,7 @@ void espi_it8xxx2_espi_reset_isr(const struct device *port,
 #define ESPI_IT8XXX2_ESPI_RESET_PIN  2
 static void espi_it8xxx2_enable_reset(void)
 {
-	struct gpio_it8xxx2_regs *const gpio_regs = GPIO_IT8XXX2_REG_BASE;
+	struct gpio_ite_ec_regs *const gpio_regs = GPIO_ITE_EC_REGS_BASE;
 	static struct gpio_callback espi_reset_cb;
 
 	/* eSPI reset is enabled on GPD2 */
@@ -2472,7 +2488,7 @@ static int espi_it8xxx2_init(const struct device *dev)
 		(struct espi_vw_regs *)config->base_espi_vw;
 	struct espi_slave_regs *const slave_reg =
 		(struct espi_slave_regs *)config->base_espi_slave;
-	struct gctrl_it8xxx2_regs *const gctrl = ESPI_IT8XXX2_GET_GCTRL_BASE;
+	struct gctrl_ite_ec_regs *const gctrl = ESPI_ITE_GET_GCTRL_BASE;
 
 	/* configure VCC detector */
 	gctrl->GCTRL_RSTS = (gctrl->GCTRL_RSTS &
@@ -2539,8 +2555,13 @@ static int espi_it8xxx2_init(const struct device *dev)
 	slave_reg->ESGCTRL2 |= IT8XXX2_ESPI_TO_WUC_ENABLE;
 
 	/* Enable WU42 of WUI */
+#ifdef CONFIG_SOC_SERIES_IT51XXX
+	it51xxx_wuc_clear_status(config->wuc.wucs, config->wuc.mask);
+	it51xxx_wuc_enable(config->wuc.wucs, config->wuc.mask);
+#else
 	it8xxx2_wuc_clear_status(config->wuc.wucs, config->wuc.mask);
 	it8xxx2_wuc_enable(config->wuc.wucs, config->wuc.mask);
+#endif
 	/*
 	 * Only register isr here, the interrupt only need to be enabled
 	 * before CPU and RAM clocks gated in the idle function.

dts/riscv/ite/it51xxx.dtsi

@@ -1189,6 +1189,31 @@
 			kso17-gpios = <&gpioc 5 (GPIO_OPEN_DRAIN | GPIO_PULL_UP)>;
 		};
 
+		espi0: espi@f03100 {
+			compatible = "ite,it8xxx2-espi";
+			reg = <0x00f03100 0xd8    /* eSPI slave */
+			       0x00f03200 0x9a    /* eSPI VW */
+			       0x00f03300 0xd0    /* eSPI Queue 0 */
+			       0x00f03400 0xc0    /* eSPI Queue 1 */
+			       0x00f01200 6       /* EC2I bridge */
+			       0x00f01300 11      /* Host KBC */
+			       0x00f01500 0x100   /* Host PMC */
+			       0x00f01000 0xd1>;  /* SMFI */
+			interrupts = <IT51XXX_IRQ_ESPI IRQ_TYPE_LEVEL_HIGH
+				      IT51XXX_IRQ_ESPI_VW IRQ_TYPE_LEVEL_HIGH
+				      IT51XXX_IRQ_KBC_IBF IRQ_TYPE_LEVEL_HIGH
+				      IT51XXX_IRQ_KBC_OBE IRQ_TYPE_LEVEL_HIGH
+				      IT51XXX_IRQ_PMC1_IBF IRQ_TYPE_LEVEL_HIGH
+				      IT51XXX_IRQ_PCH_P80 IRQ_TYPE_LEVEL_HIGH
+				      IT51XXX_IRQ_PMC2_IBF IRQ_TYPE_LEVEL_HIGH
+				      IT51XXX_IRQ_WKINTD IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-parent = <&intc>;
+			wucctrl = <&wuc_wu42>;
+			#address-cells = <1>;
+			#size-cells = <1>;
+			status = "disabled";
+		};
+
 		twd0: watchdog@f04780 {
 			compatible = "ite,it51xxx-watchdog";
 			reg = <0x00f04780 0x20>;

soc/ite/ec/it51xxx/chip_chipregs.h

@@ -267,8 +267,16 @@ struct gctrl_it51xxx_regs {
 	volatile uint8_t reserved_1d_1f[3];
 	/* 0x20: Reset Control 5 */
 	volatile uint8_t GCTRL_RSTC5;
-	/* 0x21-0x37: reserved_21_37 */
-	volatile uint8_t reserved_21_37[23];
+	/* 0x21-0x2f: reserved_21_2f */
+	volatile uint8_t reserved_21_2f[15];
+	/* 0x30: Port 80h/81h Status Register */
+	volatile uint8_t GCTRL_P80H81HSR;
+	/* 0x31: Port 80h Data Register */
+	volatile uint8_t GCTRL_P80HDR;
+	/* 0x32: Port 81h Data Register */
+	volatile uint8_t GCTRL_P81HDR;
+	/* 0x33-0x37: reserved_33_37 */
+	volatile uint8_t reserved_33_37[5];
 	/* 0x38: Special Control 9 */
 	volatile uint8_t GCTRL_SPCTRL9;
 	/* 0x39-0x46: reserved_39_46 */

soc/ite/ec/it51xxx/linker.ld

@@ -377,6 +377,19 @@ SECTIONS
 
     __data_region_end = .;
 
+	SECTION_DATA_PROLOGUE(.h2ram_pool,(NOLOAD),)
+	{
+		/*
+		 * Append h2ram_pool section at the end of used memory, so gap
+		 * due to alignment is still available for newly added variables
+		 */
+		. = ALIGN(0x1000);
+		_h2ram_pool_start = .;
+		KEEP(*(.h2ram_pool))
+		_h2ram_pool_end = .;
+	}  GROUP_DATA_LINK_IN(RAMABLE_REGION, RAMABLE_REGION)
+	_h2ram_pool_size = ABSOLUTE(_h2ram_pool_end - _h2ram_pool_start);
+
 	__kernel_ram_end = .;
 	__kernel_ram_size = __kernel_ram_end - __kernel_ram_start;
 

soc/ite/ec/it51xxx/soc.c

@@ -7,6 +7,8 @@
 #include <soc_common.h>
 #include <zephyr/kernel.h>
 
+#include "soc_espi.h"
+
 static mm_reg_t ecpm_base = DT_REG_ADDR(DT_NODELABEL(ecpm));
 /* it51xxx ECPM registers definition */
 /* 0x03: PLL Control */
@@ -57,12 +59,25 @@ void riscv_idle(enum chip_pll_mode mode, unsigned int key)
 	csr_clear(mie, MIP_MEIP);
 	sys_trace_idle();
 
+#ifdef CONFIG_ESPI
+	/*
+	 * H2RAM feature requires RAM clock to be active. Since the below doze
+	 * mode will disable CPU and RAM clocks, enable eSPI transaction
+	 * interrupt to restore clocks. With this interrupt, EC will not defer
+	 * eSPI bus while transaction is accepted.
+	 */
+	espi_ite_ec_enable_trans_irq(ESPI_ITE_SOC_DEV, true);
+#endif
 	/* Chip doze after wfi instruction */
 	chip_pll_ctrl(mode);
 
 	/* Wait for interrupt */
 	__asm__ volatile("wfi");
 
+#ifdef CONFIG_ESPI
+	/* CPU has been woken up, the interrupt is no longer needed */
+	espi_ite_ec_enable_trans_irq(ESPI_ITE_SOC_DEV, false);
+#endif
 	/*
 	 * Enable M-mode external interrupt
 	 * An interrupt can not be fired yet until we enable global interrupt