src/soc/intel/broadwell/serialio.c

/* SPDX-License-Identifier: GPL-2.0-only */
/* This file is part of the coreboot project. */

#include <device/mmio.h>
#include <device/pci_ops.h>
#include <cbmem.h>
#include <console/console.h>
#include <device/device.h>
#include <device/pci.h>
#include <device/pci_ids.h>
#include <soc/iobp.h>
#include <soc/nvs.h>
#include <soc/pci_devs.h>
#include <soc/pch.h>
#include <soc/ramstage.h>
#include <soc/rcba.h>
#include <soc/serialio.h>
#include <soc/intel/broadwell/chip.h>

/* Set D3Hot Power State in ACPI mode */
static void serialio_enable_d3hot(struct resource *res)
{
	u32 reg32 = read32(res2mmio(res, PCH_PCS, 0));
	reg32 |= PCH_PCS_PS_D3HOT;
	write32(res2mmio(res, PCH_PCS, 0), reg32);
}

static int serialio_uart_is_debug(struct device *dev)
{
#if CONFIG(INTEL_PCH_UART_CONSOLE)
	switch (dev->path.pci.devfn) {
	case PCH_DEVFN_UART0: /* UART0 */
		return !!(CONFIG_INTEL_PCH_UART_CONSOLE_NUMBER == 0);
	case PCH_DEVFN_UART1: /* UART1 */
		return !!(CONFIG_INTEL_PCH_UART_CONSOLE_NUMBER == 1);
	}
#endif
	return 0;
}

/* Enable clock in PCI mode */
static void serialio_enable_clock(struct resource *bar0)
{
	u32 reg32 = read32(res2mmio(bar0, SIO_REG_PPR_CLOCK, 0));
	reg32 |= SIO_REG_PPR_CLOCK_EN;
	write32(res2mmio(bar0, SIO_REG_PPR_CLOCK, 0), reg32);
}

/* Put Serial IO D21:F0-F6 device into desired mode. */
static void serialio_d21_mode(int sio_index, int int_pin, int acpi_mode)
{
	u32 portctrl = SIO_IOBP_PORTCTRL_PM_CAP_PRSNT;

	/* Snoop select 1. */
	portctrl |= SIO_IOBP_PORTCTRL_SNOOP_SELECT(1);

	/* Set interrupt pin. */
	portctrl |= SIO_IOBP_PORTCTRL_INT_PIN(int_pin);

	if (acpi_mode) {
		/* Enable ACPI interrupt mode. */
		portctrl |= SIO_IOBP_PORTCTRL_ACPI_IRQ_EN;

		/* Disable PCI config space. */
		portctrl |= SIO_IOBP_PORTCTRL_PCI_CONF_DIS;
	}

	pch_iobp_update(SIO_IOBP_PORTCTRLX(sio_index), 0, portctrl);
}

/* Put Serial IO D23:F0 device into desired mode. */
static void serialio_d23_mode(int acpi_mode)
{
	u32 portctrl = 0;

	/* Snoop select 1. */
	pch_iobp_update(SIO_IOBP_PORTCTRL1, 0,
			SIO_IOBP_PORTCTRL1_SNOOP_SELECT(1));

	if (acpi_mode) {
		/* Enable ACPI interrupt mode. */
		portctrl |= SIO_IOBP_PORTCTRL0_ACPI_IRQ_EN;

		/* Disable PCI config space. */
		portctrl |= SIO_IOBP_PORTCTRL0_PCI_CONF_DIS;
	}

	pch_iobp_update(SIO_IOBP_PORTCTRL0, 0, portctrl);
}

/* Enable LTR Auto Mode for D21:F1-F6. */
static void serialio_d21_ltr(struct resource *bar0)
{
	u32 reg;

	/* 1. Program BAR0 + 808h[2] = 0b */
	reg = read32(res2mmio(bar0, SIO_REG_PPR_GEN, 0));
	reg &= ~SIO_REG_PPR_GEN_LTR_MODE_MASK;
	write32(res2mmio(bar0, SIO_REG_PPR_GEN, 0), reg);

	/* 2. Program BAR0 + 804h[1:0] = 00b */
	reg = read32(res2mmio(bar0, SIO_REG_PPR_RST, 0));
	reg &= ~SIO_REG_PPR_RST_ASSERT;
	write32(res2mmio(bar0, SIO_REG_PPR_RST, 0), reg);

	/* 3. Program BAR0 + 804h[1:0] = 11b */
	reg = read32(res2mmio(bar0, SIO_REG_PPR_RST, 0));
	reg |= SIO_REG_PPR_RST_ASSERT;
	write32(res2mmio(bar0, SIO_REG_PPR_RST, 0), reg);

	/* 4. Program BAR0 + 814h[31:0] = 00000000h */
	write32(res2mmio(bar0, SIO_REG_AUTO_LTR, 0), 0);
}

/* Enable LTR Auto Mode for D23:F0. */
static void serialio_d23_ltr(struct resource *bar0)
{
	u32 reg;

	/* Program BAR0 + 1008h[2] = 1b */
	reg = read32(res2mmio(bar0, SIO_REG_SDIO_PPR_GEN, 0));
	reg |= SIO_REG_PPR_GEN_LTR_MODE_MASK;
	write32(res2mmio(bar0, SIO_REG_SDIO_PPR_GEN, 0), reg);

	/* Program BAR0 + 1010h = 0x00000000 */
	write32(res2mmio(bar0, SIO_REG_SDIO_PPR_SW_LTR, 0), 0);

	/* Program BAR0 + 3Ch[30] = 1b */
	reg = read32(res2mmio(bar0, SIO_REG_SDIO_PPR_CMD12, 0));
	reg |= SIO_REG_SDIO_PPR_CMD12_B30;
	write32(res2mmio(bar0, SIO_REG_SDIO_PPR_CMD12, 0), reg);
}

/* Select I2C voltage of 1.8V or 3.3V. */
static void serialio_i2c_voltage_sel(struct resource *bar0, u8 voltage)
{
	u32 reg32 = read32(res2mmio(bar0, SIO_REG_PPR_GEN, 0));
	reg32 &= ~SIO_REG_PPR_GEN_VOLTAGE_MASK;
	reg32 |= SIO_REG_PPR_GEN_VOLTAGE(voltage);
	write32(res2mmio(bar0, SIO_REG_PPR_GEN, 0), reg32);
}

/* Init sequence to be run once, done as part of D21:F0 (SDMA) init. */
static void serialio_init_once(int acpi_mode)
{
	if (acpi_mode) {
		/* Enable ACPI IRQ for IRQ13, IRQ7, IRQ6, IRQ5 in RCBA. */
		RCBA32_OR(ACPIIRQEN, (1 << 13)|(1 << 7)|(1 << 6)|(1 << 5));
	}

	/* Program IOBP CB000154h[12,9:8,4:0] = 1001100011111b. */
	pch_iobp_update(SIO_IOBP_GPIODF, ~0x0000131f, 0x0000131f);

	/* Program IOBP CB000180h[5:0] = 111111b (undefined register) */
	pch_iobp_update(0xcb000180, ~0x0000003f, 0x0000003f);
}

static void serialio_init(struct device *dev)
{
	config_t *config = config_of(dev);
	struct resource *bar0, *bar1;
	int sio_index = -1;
	u32 reg32;

	printk(BIOS_DEBUG, "Initializing Serial IO device\n");

	/* Ensure memory and bus master are enabled */
	reg32 = pci_read_config32(dev, PCI_COMMAND);
	reg32 |= PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY;
	pci_write_config32(dev, PCI_COMMAND, reg32);

	/* Find BAR0 and BAR1 */
	bar0 = find_resource(dev, PCI_BASE_ADDRESS_0);
	if (!bar0)
		return;
	bar1 = find_resource(dev, PCI_BASE_ADDRESS_1);
	if (!bar1)
		return;

	if (!config->sio_acpi_mode)
		serialio_enable_clock(bar0);

	switch (dev->path.pci.devfn) {
	case PCH_DEVFN_SDMA: /* SDMA */
		sio_index = SIO_ID_SDMA;
		serialio_init_once(config->sio_acpi_mode);
		serialio_d21_mode(sio_index, SIO_PIN_INTB,
				  config->sio_acpi_mode);
		break;
	case PCH_DEVFN_I2C0: /* I2C0 */
		sio_index = SIO_ID_I2C0;
		serialio_d21_ltr(bar0);
		serialio_i2c_voltage_sel(bar0, config->sio_i2c0_voltage);
		serialio_d21_mode(sio_index, SIO_PIN_INTC,
				  config->sio_acpi_mode);
		break;
	case PCH_DEVFN_I2C1: /* I2C1 */
		sio_index = SIO_ID_I2C1;
		serialio_d21_ltr(bar0);
		serialio_i2c_voltage_sel(bar0, config->sio_i2c1_voltage);
		serialio_d21_mode(sio_index, SIO_PIN_INTC,
				  config->sio_acpi_mode);
		break;
	case PCH_DEVFN_SPI0: /* SPI0 */
		sio_index = SIO_ID_SPI0;
		serialio_d21_ltr(bar0);
		serialio_d21_mode(sio_index, SIO_PIN_INTC,
				  config->sio_acpi_mode);
		break;
	case PCH_DEVFN_SPI1: /* SPI1 */
		sio_index = SIO_ID_SPI1;
		serialio_d21_ltr(bar0);
		serialio_d21_mode(sio_index, SIO_PIN_INTC,
				  config->sio_acpi_mode);
		break;
	case PCH_DEVFN_UART0: /* UART0 */
		sio_index = SIO_ID_UART0;
		if (!serialio_uart_is_debug(dev))
			serialio_d21_ltr(bar0);
		serialio_d21_mode(sio_index, SIO_PIN_INTD,
				  config->sio_acpi_mode);
		break;
	case PCH_DEVFN_UART1: /* UART1 */
		sio_index = SIO_ID_UART1;
		if (!serialio_uart_is_debug(dev))
			serialio_d21_ltr(bar0);
		serialio_d21_mode(sio_index, SIO_PIN_INTD,
				  config->sio_acpi_mode);
		break;
	case PCH_DEVFN_SDIO: /* SDIO */
		sio_index = SIO_ID_SDIO;
		serialio_d23_ltr(bar0);
		serialio_d23_mode(config->sio_acpi_mode);
		break;
	default:
		return;
	}

	if (config->sio_acpi_mode) {
		global_nvs_t *gnvs;

		/* Find ACPI NVS to update BARs */
		gnvs = (global_nvs_t *)cbmem_find(CBMEM_ID_ACPI_GNVS);
		if (!gnvs) {
			printk(BIOS_ERR, "Unable to locate Global NVS\n");
			return;
		}

		/* Save BAR0 and BAR1 to ACPI NVS */
		gnvs->dev.bar0[sio_index] = (u32)bar0->base;
		gnvs->dev.bar1[sio_index] = (u32)bar1->base;

		/* Do not enable UART if it is used as debug port */
		if (!serialio_uart_is_debug(dev))
			gnvs->dev.enable[sio_index] = 1;

		/* Put device in D3hot state via BAR1 */
		if (dev->path.pci.devfn != PCH_DEVFN_SDMA)
			serialio_enable_d3hot(bar1); /* all but SDMA */
	}
}

static void serialio_set_resources(struct device *dev)
{
	pci_dev_set_resources(dev);

#if CONFIG(INTEL_PCH_UART_CONSOLE)
	/* Update UART base address if used for debug */
	if (serialio_uart_is_debug(dev)) {
		struct resource *res = find_resource(dev, PCI_BASE_ADDRESS_0);
		if (res)
			uartmem_setbaseaddr(res->base);
	}
#endif
}

static struct device_operations device_ops = {
	.read_resources		= &pci_dev_read_resources,
	.set_resources		= &serialio_set_resources,
	.enable_resources	= &pci_dev_enable_resources,
	.init			= &serialio_init,
	.ops_pci		= &broadwell_pci_ops,
};

static const unsigned short pci_device_ids[] = {
	0x9c60, 0x9ce0, /* 0:15.0 - SDMA */
	0x9c61, 0x9ce1, /* 0:15.1 - I2C0 */
	0x9c62, 0x9ce2, /* 0:15.2 - I2C1 */
	0x9c65, 0x9ce5, /* 0:15.3 - SPI0 */
	0x9c66, 0x9ce6, /* 0:15.4 - SPI1 */
	0x9c63, 0x9ce3, /* 0:15.5 - UART0 */
	0x9c64, 0x9ce4, /* 0:15.6 - UART1 */
	0x9c35, 0x9cb5, /* 0:17.0 - SDIO */
	0
};

static const struct pci_driver pch_pcie __pci_driver = {
	.ops	 = &device_ops,
	.vendor	 = PCI_VENDOR_ID_INTEL,
	.devices = pci_device_ids,
};