x86: broadwell: Add a pinctrl driver

GPIO pins need to be set up on start-up. Add a driver to provide this,
configured from the device tree.

The binding is slightly different from the existing ICH6 binding, since that
is quite verbose. The new binding should be just as extensible.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Bin Meng <bmeng.cn@gmail.com>

2 files changed, 279 insertions, 0 deletions

diff --git a/arch/x86/cpu/broadwell/Makefile b/arch/x86/cpu/broadwell/Makefile
index 128829a..db60e30 100644
--- a/arch/x86/cpu/broadwell/Makefile
+++ b/arch/x86/cpu/broadwell/Makefile
@@ -7,3 +7,4 @@
 obj-y += cpu.o
 obj-y += iobp.o
 obj-y += pch.o
+obj-y += pinctrl_broadwell.o
diff --git a/arch/x86/cpu/broadwell/pinctrl_broadwell.c b/arch/x86/cpu/broadwell/pinctrl_broadwell.c
new file mode 100644
index 0000000..2a3fced
--- /dev/null
+++ b/arch/x86/cpu/broadwell/pinctrl_broadwell.c
@@ -0,0 +1,278 @@
+/*
+ * Copyright (C) 2016 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <pch.h>
+#include <pci.h>
+#include <asm/cpu.h>
+#include <asm/gpio.h>
+#include <asm/io.h>
+#include <asm/pci.h>
+#include <asm/arch/gpio.h>
+#include <dt-bindings/gpio/x86-gpio.h>
+#include <dm/pinctrl.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+enum {
+	MAX_GPIOS	= 95,
+};
+
+#define PIRQ_SHIFT	16
+#define CONF_MASK	0xffff
+
+struct pin_info {
+	int node;
+	int phandle;
+	bool mode_gpio;
+	bool dir_input;
+	bool invert;
+	bool trigger_level;
+	bool output_high;
+	bool sense_disable;
+	bool owner_gpio;
+	bool route_smi;
+	bool irq_enable;
+	bool reset_rsmrst;
+	bool pirq_apic_route;
+};
+
+static int broadwell_pinctrl_read_configs(struct udevice *dev,
+					  struct pin_info *conf, int max_pins)
+{
+	const void *blob = gd->fdt_blob;
+	int count = 0;
+	int node;
+
+	debug("%s: starting\n", __func__);
+	for (node = fdt_first_subnode(blob, dev->of_offset);
+	     node > 0;
+	     node = fdt_next_subnode(blob, node)) {
+		int phandle = fdt_get_phandle(blob, node);
+
+		if (!phandle)
+			continue;
+		if (count == max_pins)
+			return -ENOSPC;
+
+		/* We've found a new configuration */
+		memset(conf, '\0', sizeof(*conf));
+		conf->node = node;
+		conf->phandle = phandle;
+		conf->mode_gpio = fdtdec_get_bool(blob, node, "mode-gpio");
+		if (fdtdec_get_int(blob, node, "direction", -1) == PIN_INPUT)
+			conf->dir_input = true;
+		conf->invert = fdtdec_get_bool(blob, node, "invert");
+		if (fdtdec_get_int(blob, node, "trigger", -1) == TRIGGER_LEVEL)
+			conf->trigger_level = true;
+		if (fdtdec_get_int(blob, node, "output-value", -1) == 1)
+			conf->output_high = true;
+		conf->sense_disable = fdtdec_get_bool(blob, node,
+						      "sense-disable");
+		if (fdtdec_get_int(blob, node, "owner", -1) == OWNER_GPIO)
+			conf->owner_gpio = true;
+		if (fdtdec_get_int(blob, node, "route", -1) == ROUTE_SMI)
+			conf->route_smi = true;
+		conf->irq_enable = fdtdec_get_bool(blob, node, "irq-enable");
+		conf->reset_rsmrst = fdtdec_get_bool(blob, node,
+						     "reset-rsmrst");
+		if (fdtdec_get_int(blob, node, "pirq-apic", -1) ==
+				PIRQ_APIC_ROUTE)
+			conf->pirq_apic_route = true;
+		debug("config: phandle=%d\n", phandle);
+		count++;
+		conf++;
+	}
+	debug("%s: Found %d configurations\n", __func__, count);
+
+	return count;
+}
+
+static int broadwell_pinctrl_lookup_phandle(struct pin_info *conf,
+					    int conf_count, int phandle)
+{
+	int i;
+
+	for (i = 0; i < conf_count; i++) {
+		if (conf[i].phandle == phandle)
+			return i;
+	}
+
+	return -ENOENT;
+}
+
+static int broadwell_pinctrl_read_pins(struct udevice *dev,
+		struct pin_info *conf, int conf_count, int gpio_conf[],
+		int num_gpios)
+{
+	const void *blob = gd->fdt_blob;
+	int count = 0;
+	int node;
+
+	for (node = fdt_first_subnode(blob, dev->of_offset);
+	     node > 0;
+	     node = fdt_next_subnode(blob, node)) {
+		int len, i;
+		const u32 *prop = fdt_getprop(blob, node, "config", &len);
+
+		if (!prop)
+			continue;
+
+		/* There are three cells per pin */
+		count = len / (sizeof(u32) * 3);
+		debug("Found %d GPIOs to configure\n", count);
+		for (i = 0; i < count; i++) {
+			uint gpio = fdt32_to_cpu(prop[i * 3]);
+			uint phandle = fdt32_to_cpu(prop[i * 3 + 1]);
+			int val;
+
+			if (gpio >= num_gpios) {
+				debug("%s: GPIO %d out of range\n", __func__,
+				      gpio);
+				return -EDOM;
+			}
+			val = broadwell_pinctrl_lookup_phandle(conf, conf_count,
+							       phandle);
+			if (val < 0) {
+				debug("%s: Cannot find phandle %d\n", __func__,
+				      phandle);
+				return -EINVAL;
+			}
+			gpio_conf[gpio] = val |
+				fdt32_to_cpu(prop[i * 3 + 2]) << PIRQ_SHIFT;
+		}
+	}
+
+	return 0;
+}
+
+static void broadwell_pinctrl_commit(struct pch_lp_gpio_regs *regs,
+				     struct pin_info *pin_info,
+				     int gpio_conf[], int count)
+{
+	u32 owner_gpio[GPIO_BANKS] = {0};
+	u32 route_smi[GPIO_BANKS] = {0};
+	u32 irq_enable[GPIO_BANKS] = {0};
+	u32 reset_rsmrst[GPIO_BANKS] = {0};
+	u32 pirq2apic = 0;
+	int set, bit, gpio = 0;
+
+	for (gpio = 0; gpio < MAX_GPIOS; gpio++) {
+		int confnum = gpio_conf[gpio] & CONF_MASK;
+		struct pin_info *pin = &pin_info[confnum];
+		u32 val;
+
+		val = pin->mode_gpio << CONFA_MODE_SHIFT |
+			pin->dir_input << CONFA_DIR_SHIFT |
+			pin->invert << CONFA_INVERT_SHIFT |
+			pin->trigger_level << CONFA_TRIGGER_SHIFT |
+			pin->output_high << CONFA_OUTPUT_SHIFT;
+		outl(val, &regs->config[gpio].conf_a);
+		outl(pin->sense_disable << CONFB_SENSE_SHIFT,
+		     &regs->config[gpio].conf_b);
+
+		/* Determine set and bit based on GPIO number */
+		set = gpio / GPIO_PER_BANK;
+		bit = gpio % GPIO_PER_BANK;
+
+		/* Apply settings to set specific bits */
+		owner_gpio[set] |= pin->owner_gpio << bit;
+		route_smi[set] |= pin->route_smi << bit;
+		irq_enable[set] |= pin->irq_enable << bit;
+		reset_rsmrst[set] |= pin->reset_rsmrst << bit;
+
+		/* PIRQ to IO-APIC map */
+		if (pin->pirq_apic_route)
+			pirq2apic |= gpio_conf[gpio] >> PIRQ_SHIFT;
+		debug("gpio %d: conf %d, mode_gpio %d, dir_input %d, output_high %d\n",
+		      gpio, confnum, pin->mode_gpio, pin->dir_input,
+		      pin->output_high);
+	}
+
+	for (set = 0; set < GPIO_BANKS; set++) {
+		outl(owner_gpio[set], &regs->own[set]);
+		outl(route_smi[set], &regs->gpi_route[set]);
+		outl(irq_enable[set], &regs->gpi_ie[set]);
+		outl(reset_rsmrst[set], &regs->rst_sel[set]);
+	}
+
+	outl(pirq2apic, &regs->pirq_to_ioxapic);
+}
+
+static int broadwell_pinctrl_probe(struct udevice *dev)
+{
+	struct pch_lp_gpio_regs *regs;
+	struct pin_info conf[12];
+	int gpio_conf[MAX_GPIOS];
+	struct udevice *pch;
+	int conf_count;
+	u32 gpiobase;
+	int ret;
+
+	ret = uclass_first_device(UCLASS_PCH, &pch);
+	if (ret)
+		return ret;
+	if (!pch)
+		return -ENODEV;
+	debug("%s: start\n", __func__);
+
+	/* Only init once, before relocation */
+	if (gd->flags & GD_FLG_RELOC)
+		return 0;
+
+	/*
+	 * Get the memory/io base address to configure every pins.
+	 * IOBASE is used to configure the mode/pads
+	 * GPIOBASE is used to configure the direction and default value
+	 */
+	ret = pch_get_gpio_base(pch, &gpiobase);
+	if (ret) {
+		debug("%s: invalid GPIOBASE address (%08x)\n", __func__,
+		      gpiobase);
+		return -EINVAL;
+	}
+
+	conf_count = broadwell_pinctrl_read_configs(dev, conf,
+						    ARRAY_SIZE(conf));
+	if (conf_count < 0) {
+		debug("%s: Cannot read configs: err=%d\n", __func__, ret);
+		return conf_count;
+	}
+
+	/*
+	 * Assume that pin settings are provided for every pin. Pins not
+	 * mentioned will get the first config mentioned in the list.
+	 */
+	ret = broadwell_pinctrl_read_pins(dev, conf, conf_count, gpio_conf,
+					  MAX_GPIOS);
+	if (ret) {
+		debug("%s: Cannot read pin settings: err=%d\n", __func__, ret);
+		return ret;
+	}
+
+	regs = (struct pch_lp_gpio_regs *)gpiobase;
+	broadwell_pinctrl_commit(regs, conf, gpio_conf, ARRAY_SIZE(conf));
+
+	debug("%s: done\n", __func__);
+
+	return 0;
+}
+
+static const struct udevice_id broadwell_pinctrl_match[] = {
+	{ .compatible = "intel,x86-broadwell-pinctrl",
+		.data = X86_SYSCON_PINCONF },
+	{ /* sentinel */ }
+};
+
+U_BOOT_DRIVER(broadwell_pinctrl) = {
+	.name = "broadwell_pinctrl",
+	.id = UCLASS_SYSCON,
+	.of_match = broadwell_pinctrl_match,
+	.probe = broadwell_pinctrl_probe,
+};