x86: ich6-gpio: Add Intel Tunnel Creek GPIO support

Intel Tunnel Creek GPIO register block is compatible with current
ich6-gpio driver, except the offset and content of GPIO block base
address register in the LPC PCI configuration space are different.

Use u16 instead of u32 to store the 16-bit I/O address of the GPIO
registers so that it could support both Ivybridge and Tunnel Creek.

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

arch/x86/include/asm/arch-queensbay/gpio.h

@@ -0,0 +1,13 @@
+/*
+ * Copyright (C) 2014, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _X86_ARCH_GPIO_H_
+#define _X86_ARCH_GPIO_H_
+
+/* Where in config space is the register that points to the GPIO registers? */
+#define PCI_CFG_GPIOBASE 0x44
+
+#endif /* _X86_ARCH_GPIO_H_ */

arch/x86/include/asm/gpio.h

@@ -11,7 +11,7 @@
 #include <asm-generic/gpio.h>
 
 struct ich6_bank_platdata {
-	uint32_t base_addr;
+	uint16_t base_addr;
 	const char *bank_name;
 };
 
@@ -147,7 +147,7 @@ struct pch_gpio_map {
 	} set3;
 };
 
-void setup_pch_gpios(u32 gpiobase, const struct pch_gpio_map *gpio);
+void setup_pch_gpios(u16 gpiobase, const struct pch_gpio_map *gpio);
 void ich_gpio_set_gpio_map(const struct pch_gpio_map *map);
 
 #endif /* _X86_GPIO_H_ */

board/coreboot/coreboot/coreboot.c

@@ -16,7 +16,7 @@ int arch_early_init_r(void)
 	return 0;
 }
 
-void setup_pch_gpios(u32 gpiobase, const struct pch_gpio_map *gpio)
+void setup_pch_gpios(u16 gpiobase, const struct pch_gpio_map *gpio)
 {
 	return;
 }

board/google/chromebook_link/link.c

@@ -125,7 +125,7 @@ int board_early_init_f(void)
 	return 0;
 }
 
-void setup_pch_gpios(u32 gpiobase, const struct pch_gpio_map *gpio)
+void setup_pch_gpios(u16 gpiobase, const struct pch_gpio_map *gpio)
 {
 	/* GPIO Set 1 */
 	if (gpio->set1.level)

board/intel/crownbay/crownbay.c

@@ -19,3 +19,8 @@ int board_early_init_f(void)
 
 	return 0;
 }
+
+void setup_pch_gpios(u16 gpiobase, const struct pch_gpio_map *gpio)
+{
+	return;
+}

drivers/gpio/intel_ich6_gpio.c

@@ -39,9 +39,9 @@
 
 struct ich6_bank_priv {
 	/* These are I/O addresses */
-	uint32_t use_sel;
-	uint32_t io_sel;
-	uint32_t lvl;
+	uint16_t use_sel;
+	uint16_t io_sel;
+	uint16_t lvl;
 };
 
 /* TODO: Move this to device tree, or platform data */
@@ -57,7 +57,7 @@ static int gpio_ich6_ofdata_to_platdata(struct udevice *dev)
 	u8 tmpbyte;
 	u16 tmpword;
 	u32 tmplong;
-	u32 gpiobase;
+	u16 gpiobase;
 	int offset;
 
 	/* Where should it be? */
@@ -116,11 +116,15 @@ static int gpio_ich6_ofdata_to_platdata(struct udevice *dev)
 	/*
 	 * GPIOBASE moved to its current offset with ICH6, but prior to
 	 * that it was unused (or undocumented). Check that it looks
-	 * okay: not all ones or zeros, and mapped to I/O space (bit 0).
+	 * okay: not all ones or zeros.
+	 *
+	 * Note we don't need check bit0 here, because the Tunnel Creek
+	 * GPIO base address register bit0 is reserved (read returns 0),
+	 * while on the Ivybridge the bit0 is used to indicate it is an
+	 * I/O space.
 	 */
 	tmplong = pci_read_config32(pci_dev, PCI_CFG_GPIOBASE);
-	if (tmplong == 0x00000000 || tmplong == 0xffffffff ||
-	    !(tmplong & 0x00000001)) {
+	if (tmplong == 0x00000000 || tmplong == 0xffffffff) {
 		debug("%s: unexpected GPIOBASE value\n", __func__);
 		return -ENODEV;
 	}
@@ -131,7 +135,7 @@ static int gpio_ich6_ofdata_to_platdata(struct udevice *dev)
 	 * at the offset that we just read. Bit 0 indicates that it's
 	 * an I/O address, not a memory address, so mask that off.
 	 */
-	gpiobase = tmplong & 0xfffffffe;
+	gpiobase = tmplong & 0xfffe;
 	offset = fdtdec_get_int(gd->fdt_blob, dev->of_offset, "reg", -1);
 	if (offset == -1) {
 		debug("%s: Invalid register offset %d\n", __func__, offset);