sh: pci: Initial PCI-Express support for SH7786 Urquell board.

This adds initial support for the PCI-Express module in the SH7786,
particularly as it relates to the urquell platform. Presently it is
only supported in root complex mode, with endpoint mode still requiring
more debugging. 29/32-bit mode and lane configurations are selectable via
board mode pins, and are otherwise fixed.

Only 4x and 1x PCI channels are presently handled, the PCI bridge still
requires additional debugging and stabilization in hardware.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

3 files changed, 357 insertions, 0 deletions

diff --git a/arch/sh/boards/Kconfig b/arch/sh/boards/Kconfig
index 1c91b1f565d..2b1af0eefa6 100644
--- a/arch/sh/boards/Kconfig
+++ b/arch/sh/boards/Kconfig
@@ -175,6 +175,7 @@ config SH_URQUELL
 	bool "Urquell"
 	depends on CPU_SUBTYPE_SH7786
 	select ARCH_REQUIRE_GPIOLIB
+	select SYS_SUPPORTS_PCI
 
 config SH_MIGOR
 	bool "Migo-R"
diff --git a/arch/sh/drivers/pci/Makefile b/arch/sh/drivers/pci/Makefile
index d6303d0e494..08af1f45975 100644
--- a/arch/sh/drivers/pci/Makefile
+++ b/arch/sh/drivers/pci/Makefile
@@ -25,3 +25,4 @@ obj-$(CONFIG_SH_TITAN)			+= fixups-titan.o
 obj-$(CONFIG_SH_LANDISK)		+= fixups-landisk.o
 obj-$(CONFIG_SH_LBOX_RE2)		+= fixups-rts7751r2d.o
 obj-$(CONFIG_SH_CAYMAN)			+= fixups-cayman.o
+obj-$(CONFIG_SH_URQUELL)		+= pcie-sh7786.o
diff --git a/arch/sh/drivers/pci/pcie-sh7786.c b/arch/sh/drivers/pci/pcie-sh7786.c
new file mode 100644
index 00000000000..ac37ee879ba
--- /dev/null
+++ b/arch/sh/drivers/pci/pcie-sh7786.c
@@ -0,0 +1,355 @@
+/*
+ * Low-Level PCI Express Support for the SH7786
+ *
+ *  Copyright (C) 2009  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include "pcie-sh7786.h"
+#include <asm/sizes.h>
+
+struct sh7786_pcie_port {
+	struct pci_channel	*hose;
+	unsigned int		index;
+	int			endpoint;
+	int			link;
+};
+
+static struct sh7786_pcie_port *sh7786_pcie_ports;
+static unsigned int nr_ports;
+
+static struct sh7786_pcie_hwops {
+	int (*core_init)(void);
+	int (*port_init_hw)(struct sh7786_pcie_port *port);
+} *sh7786_pcie_hwops;
+
+static struct resource sh7786_pci_32bit_mem_resources[] = {
+	{
+		.name	= "pci0_mem",
+		.start	= SH4A_PCIMEM_BASEA,
+		.end	= SH4A_PCIMEM_BASEA + SZ_64M - 1,
+		.flags	= IORESOURCE_MEM,
+	}, {
+		.name	= "pci1_mem",
+		.start	= SH4A_PCIMEM_BASEA1,
+		.end	= SH4A_PCIMEM_BASEA1 + SZ_64M - 1,
+		.flags	= IORESOURCE_MEM,
+	}, {
+		.name	= "pci2_mem",
+		.start	= SH4A_PCIMEM_BASEA2,
+		.end	= SH4A_PCIMEM_BASEA2 + SZ_64M - 1,
+		.flags	= IORESOURCE_MEM,
+	},
+};
+
+static struct resource sh7786_pci_29bit_mem_resource = {
+	.start	= SH4A_PCIMEM_BASE,
+	.end	= SH4A_PCIMEM_BASE + SZ_64M - 1,
+	.flags	= IORESOURCE_MEM,
+};
+
+static struct resource sh7786_pci_io_resources[] = {
+	{
+		.name	= "pci0_io",
+		.start	= SH4A_PCIIO_BASE,
+		.end	= SH4A_PCIIO_BASE + SZ_8M - 1,
+		.flags	= IORESOURCE_IO,
+	}, {
+		.name	= "pci1_io",
+		.start	= SH4A_PCIIO_BASE1,
+		.end	= SH4A_PCIIO_BASE1 + SZ_8M - 1,
+		.flags	= IORESOURCE_IO,
+	}, {
+		.name	= "pci2_io",
+		.start	= SH4A_PCIIO_BASE2,
+		.end	= SH4A_PCIIO_BASE2 + SZ_4M - 1,
+		.flags	= IORESOURCE_IO,
+	},
+};
+
+extern struct pci_ops sh7786_pci_ops;
+
+#define DEFINE_CONTROLLER(start, idx)				\
+{								\
+	.pci_ops	= &sh7786_pci_ops,			\
+	.reg_base	= start,				\
+	/* mem_resource filled in at probe time */		\
+	.mem_offset	= 0,					\
+	.io_resource	= &sh7786_pci_io_resources[idx],	\
+	.io_offset	= 0,					\
+}
+
+static struct pci_channel sh7786_pci_channels[] = {
+	DEFINE_CONTROLLER(0xfe000000, 0),
+	DEFINE_CONTROLLER(0xfe200000, 1),
+	DEFINE_CONTROLLER(0xfcc00000, 2),
+};
+
+static int phy_wait_for_ack(struct pci_channel *chan)
+{
+	unsigned int timeout = 100;
+
+	while (timeout--) {
+		if (pci_read_reg(chan, SH4A_PCIEPHYADRR) & (1 << BITS_ACK))
+			return 0;
+
+		udelay(100);
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int pci_wait_for_irq(struct pci_channel *chan, unsigned int mask)
+{
+	unsigned int timeout = 100;
+
+	while (timeout--) {
+		if ((pci_read_reg(chan, SH4A_PCIEINTR) & mask) == mask)
+			return 0;
+
+		udelay(100);
+	}
+
+	return -ETIMEDOUT;
+}
+
+static void phy_write_reg(struct pci_channel *chan, unsigned int addr,
+			  unsigned int lane, unsigned int data)
+{
+	unsigned long phyaddr, ctrl;
+
+	phyaddr = (1 << BITS_CMD) + ((lane & 0xf) << BITS_LANE) +
+			((addr & 0xff) << BITS_ADR);
+
+	/* Enable clock */
+	ctrl = pci_read_reg(chan, SH4A_PCIEPHYCTLR);
+	ctrl |= (1 << BITS_CKE);
+	pci_write_reg(chan, ctrl, SH4A_PCIEPHYCTLR);
+
+	/* Set write data */
+	pci_write_reg(chan, data, SH4A_PCIEPHYDOUTR);
+	pci_write_reg(chan, phyaddr, SH4A_PCIEPHYADRR);
+
+	phy_wait_for_ack(chan);
+
+	/* Clear command */
+	pci_write_reg(chan, 0, SH4A_PCIEPHYADRR);
+
+	phy_wait_for_ack(chan);
+
+	/* Disable clock */
+	ctrl = pci_read_reg(chan, SH4A_PCIEPHYCTLR);
+	ctrl &= ~(1 << BITS_CKE);
+	pci_write_reg(chan, ctrl, SH4A_PCIEPHYCTLR);
+}
+
+static int phy_init(struct pci_channel *chan)
+{
+	unsigned int timeout = 100;
+
+	/* Initialize the phy */
+	phy_write_reg(chan, 0x60, 0xf, 0x004b008b);
+	phy_write_reg(chan, 0x61, 0xf, 0x00007b41);
+	phy_write_reg(chan, 0x64, 0xf, 0x00ff4f00);
+	phy_write_reg(chan, 0x65, 0xf, 0x09070907);
+	phy_write_reg(chan, 0x66, 0xf, 0x00000010);
+	phy_write_reg(chan, 0x74, 0xf, 0x0007001c);
+	phy_write_reg(chan, 0x79, 0xf, 0x01fc000d);
+
+	/* Deassert Standby */
+	phy_write_reg(chan, 0x67, 0xf, 0x00000400);
+
+	while (timeout--) {
+		if (pci_read_reg(chan, SH4A_PCIEPHYSR))
+			return 0;
+
+		udelay(100);
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int pcie_init(struct sh7786_pcie_port *port)
+{
+	struct pci_channel *chan = port->hose;
+	unsigned int data;
+	int ret;
+
+	/* Begin initialization */
+	pci_write_reg(chan, 0, SH4A_PCIETCTLR);
+
+	/* Initialize as type1. */
+	data = pci_read_reg(chan, SH4A_PCIEPCICONF3);
+	data &= ~(0x7f << 16);
+	data |= PCI_HEADER_TYPE_BRIDGE << 16;
+	pci_write_reg(chan, data, SH4A_PCIEPCICONF3);
+
+	/* Initialize default capabilities. */
+	data = pci_read_reg(chan, SH4A_PCIEEXPCAP0);
+	data &= ~(PCI_EXP_FLAGS_TYPE << 16);
+
+	if (port->endpoint)
+		data |= PCI_EXP_TYPE_ENDPOINT << 20;
+	else
+		data |= PCI_EXP_TYPE_ROOT_PORT << 20;
+
+	data |= PCI_CAP_ID_EXP;
+	pci_write_reg(chan, data, SH4A_PCIEEXPCAP0);
+
+	/* Enable x4 link width and extended sync. */
+	data = pci_read_reg(chan, SH4A_PCIEEXPCAP4);
+	data &= ~(PCI_EXP_LNKSTA_NLW << 16);
+	data |= (1 << 22) | PCI_EXP_LNKCTL_ES;
+	pci_write_reg(chan, data, SH4A_PCIEEXPCAP4);
+
+	/* Set the completion timer timeout to the maximum 32ms. */
+	data = pci_read_reg(chan, SH4A_PCIETLCTLR);
+	data &= ~0xffff;
+	data |= 0x32 << 8;
+	pci_write_reg(chan, data, SH4A_PCIETLCTLR);
+
+	/*
+	 * Set fast training sequences to the maximum 255,
+	 * and enable MAC data scrambling.
+	 */
+	data = pci_read_reg(chan, SH4A_PCIEMACCTLR);
+	data &= ~PCIEMACCTLR_SCR_DIS;
+	data |= (0xff << 16);
+	pci_write_reg(chan, data, SH4A_PCIEMACCTLR);
+
+	/* Finish initialization */
+	data = pci_read_reg(chan, SH4A_PCIETCTLR);
+	data |= 0x1;
+	pci_write_reg(chan, data, SH4A_PCIETCTLR);
+
+	/* Enable DL_Active Interrupt generation */
+	data = pci_read_reg(chan, SH4A_PCIEDLINTENR);
+	data |= PCIEDLINTENR_DLL_ACT_ENABLE;
+	pci_write_reg(chan, data, SH4A_PCIEDLINTENR);
+
+	/* Disable MAC data scrambling. */
+	data = pci_read_reg(chan, SH4A_PCIEMACCTLR);
+	data |= PCIEMACCTLR_SCR_DIS | (0xff << 16);
+	pci_write_reg(chan, data, SH4A_PCIEMACCTLR);
+
+	ret = pci_wait_for_irq(chan, MASK_INT_TX_CTRL);
+	if (unlikely(ret != 0))
+		return -ENODEV;
+
+	pci_write_reg(chan, 0x00100007, SH4A_PCIEPCICONF1);
+	pci_write_reg(chan, 0x80888000, SH4A_PCIETXVC0DCTLR);
+	pci_write_reg(chan, 0x00222000, SH4A_PCIERXVC0DCTLR);
+	pci_write_reg(chan, 0x000050A0, SH4A_PCIEEXPCAP2);
+
+	wmb();
+
+	data = pci_read_reg(chan, SH4A_PCIEMACSR);
+	printk(KERN_NOTICE "PCI: PCIe#%d link width %d\n",
+	       port->index, (data >> 20) & 0x3f);
+
+	pci_write_reg(chan, 0x007c0000, SH4A_PCIEPAMR0);
+	pci_write_reg(chan, 0x00000000, SH4A_PCIEPARH0);
+	pci_write_reg(chan, 0x00000000, SH4A_PCIEPARL0);
+	pci_write_reg(chan, 0x80000100, SH4A_PCIEPTCTLR0);
+
+	pci_write_reg(chan, 0x03fc0000, SH4A_PCIEPAMR2);
+	pci_write_reg(chan, 0x00000000, SH4A_PCIEPARH2);
+	pci_write_reg(chan, 0x00000000, SH4A_PCIEPARL2);
+	pci_write_reg(chan, 0x80000000, SH4A_PCIEPTCTLR2);
+
+	return 0;
+}
+
+int __init pcibios_map_platform_irq(struct pci_dev *pdev, u8 slot, u8 pin)
+{
+        return 71;
+}
+
+static int sh7786_pcie_core_init(void)
+{
+	/* Return the number of ports */
+	return test_mode_pin(MODE_PIN12) ? 3 : 2;
+}
+
+static int __devinit sh7786_pcie_init_hw(struct sh7786_pcie_port *port)
+{
+	int ret;
+
+	ret = phy_init(port->hose);
+	if (unlikely(ret < 0))
+		return ret;
+
+	/*
+	 * Check if we are configured in endpoint or root complex mode,
+	 * this is a fixed pin setting that applies to all PCIe ports.
+	 */
+	port->endpoint = test_mode_pin(MODE_PIN11);
+
+	ret = pcie_init(port);
+	if (unlikely(ret < 0))
+		return ret;
+
+	register_pci_controller(port->hose);
+
+	return 0;
+}
+
+static struct sh7786_pcie_hwops sh7786_65nm_pcie_hwops __initdata = {
+	.core_init	= sh7786_pcie_core_init,
+	.port_init_hw	= sh7786_pcie_init_hw,
+};
+
+static int __init sh7786_pcie_init(void)
+{
+	int ret = 0, i;
+
+	printk(KERN_NOTICE "PCI: Starting intialization.\n");
+
+	sh7786_pcie_hwops = &sh7786_65nm_pcie_hwops;
+
+	nr_ports = sh7786_pcie_hwops->core_init();
+	BUG_ON(nr_ports > ARRAY_SIZE(sh7786_pci_channels));
+
+	if (unlikely(nr_ports == 0))
+		return -ENODEV;
+
+	sh7786_pcie_ports = kzalloc(nr_ports * sizeof(struct sh7786_pcie_port),
+				    GFP_KERNEL);
+	if (unlikely(!sh7786_pcie_ports))
+		return -ENOMEM;
+
+	printk(KERN_NOTICE "PCI: probing %d ports.\n", nr_ports);
+
+	for (i = 0; i < nr_ports; i++) {
+		struct sh7786_pcie_port *port = sh7786_pcie_ports + i;
+
+		port->index		= i;
+		port->hose		= sh7786_pci_channels + i;
+		port->hose->io_map_base	= port->hose->io_resource->start;
+
+		/*
+		 * Check if we are booting in 29 or 32-bit mode
+		 *
+		 * 32-bit mode provides each controller with its own
+		 * memory window, while 29-bit mode uses a shared one.
+		 */
+		port->hose->mem_resource = test_mode_pin(MODE_PIN10) ?
+			&sh7786_pci_32bit_mem_resources[i] :
+			&sh7786_pci_29bit_mem_resource;
+
+		ret |= sh7786_pcie_hwops->port_init_hw(port);
+	}
+
+	if (unlikely(ret))
+		return ret;
+
+	return 0;
+}
+arch_initcall(sh7786_pcie_init);