[MIPS] PMC MSP71xx PCI support

Patch to add PCI support for the PMC-Sierra MSP71xx devices.

Signed-off-by: Marc St-Jean <Marc_St-Jean@pmc-sierra.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 994 insertions, 0 deletions

diff --git a/arch/mips/pci/ops-pmcmsp.c b/arch/mips/pci/ops-pmcmsp.c
new file mode 100644
index 000000000000..09fa007c1d1b
--- /dev/null
+++ b/arch/mips/pci/ops-pmcmsp.c
@@ -0,0 +1,994 @@
+/*
+ * PMC-Sierra MSP board specific pci_ops
+ *
+ * Copyright 2001 MontaVista Software Inc.
+ * Copyright 2005-2007 PMC-Sierra, Inc
+ *
+ * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
+ *
+ * Much of the code is derived from the original DDB5074 port by
+ * Geert Uytterhoeven <geert@sonycom.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ *
+ */
+
+#define PCI_COUNTERS	1
+
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+
+#if defined(CONFIG_PROC_FS) && defined(PCI_COUNTERS)
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#endif /* CONFIG_PROC_FS && PCI_COUNTERS */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+
+#include <asm/byteorder.h>
+#if defined(CONFIG_PMC_MSP7120_GW) || defined(CONFIG_PMC_MSP7120_EVAL)
+#include <asm/mipsmtregs.h>
+#endif
+
+#include <msp_prom.h>
+#include <msp_cic_int.h>
+#include <msp_pci.h>
+#include <msp_regs.h>
+#include <msp_regops.h>
+
+#define PCI_ACCESS_READ		0
+#define PCI_ACCESS_WRITE	1
+
+#if defined(CONFIG_PROC_FS) && defined(PCI_COUNTERS)
+static char proc_init;
+extern struct proc_dir_entry *proc_bus_pci_dir;
+unsigned int pci_int_count[32];
+
+static void pci_proc_init(void);
+
+/*****************************************************************************
+ *
+ *  FUNCTION: read_msp_pci_counts
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Prints the count of how many times each PCI
+ *               interrupt has asserted. Can be invoked by the
+ *               /proc filesystem.
+ *
+ *  INPUTS:      page    - part of STDOUT calculation
+ *               off     - part of STDOUT calculation
+ *               count   - part of STDOUT calculation
+ *               data    - unused
+ *
+ *  OUTPUTS:     start   - new start location
+ *               eof     - end of file pointer
+ *
+ *  RETURNS:     len     - STDOUT length
+ *
+ ****************************************************************************/
+static int read_msp_pci_counts(char *page, char **start, off_t off,
+				int count, int *eof, void *data)
+{
+	int i;
+	int len = 0;
+	unsigned int intcount, total = 0;
+
+	for (i = 0; i < 32; ++i) {
+		intcount = pci_int_count[i];
+		if (intcount != 0) {
+			len += sprintf(page + len, "[%d] = %u\n", i, intcount);
+			total += intcount;
+		}
+	}
+
+	len += sprintf(page + len, "total = %u\n", total);
+	if (len <= off+count)
+		*eof = 1;
+
+	*start = page + off;
+	len -= off;
+	if (len > count)
+		len = count;
+	if (len < 0)
+		len = 0;
+
+	return len;
+}
+
+/*****************************************************************************
+ *
+ *  FUNCTION: gen_pci_cfg_wr
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Generates a configuration write cycle for debug purposes.
+ *               The IDSEL line asserted and location and data written are
+ *               immaterial. Just want to be able to prove that a
+ *               configuration write can be correctly generated on the
+ *               PCI bus.  Intent is that this function by invocable from
+ *               the /proc filesystem.
+ *
+ *  INPUTS:      page    - part of STDOUT calculation
+ *               off     - part of STDOUT calculation
+ *               count   - part of STDOUT calculation
+ *               data    - unused
+ *
+ *  OUTPUTS:     start   - new start location
+ *               eof     - end of file pointer
+ *
+ *  RETURNS:     len     - STDOUT length
+ *
+ ****************************************************************************/
+static int gen_pci_cfg_wr(char *page, char **start, off_t off,
+				int count, int *eof, void *data)
+{
+	unsigned char where = 0; /* Write to static Device/Vendor ID */
+	unsigned char bus_num = 0; /* Bus 0 */
+	unsigned char dev_fn = 0xF; /* Arbitrary device number */
+	u32 wr_data = 0xFF00AA00; /* Arbitrary data */
+	struct msp_pci_regs *preg = (void *)PCI_BASE_REG;
+	int len = 0;
+	unsigned long value;
+	int intr;
+
+	len += sprintf(page + len, "PMC MSP PCI: Beginning\n");
+
+	if (proc_init == 0) {
+		pci_proc_init();
+		proc_init = ~0;
+	}
+
+	len += sprintf(page + len, "PMC MSP PCI: Before Cfg Wr\n");
+
+	/*
+	 * Generate PCI Configuration Write Cycle
+	 */
+
+	/* Clear cause register bits */
+	preg->if_status = ~(BPCI_IFSTATUS_BC0F | BPCI_IFSTATUS_BC1F);
+
+	/* Setup address that is to appear on PCI bus */
+	preg->config_addr = BPCI_CFGADDR_ENABLE |
+		(bus_num << BPCI_CFGADDR_BUSNUM_SHF) |
+		(dev_fn << BPCI_CFGADDR_FUNCTNUM_SHF) |
+		(where & 0xFC);
+
+	value = cpu_to_le32(wr_data);
+
+	/* Launch the PCI configuration write cycle */
+	*PCI_CONFIG_SPACE_REG = value;
+
+	/*
+	 * Check if the PCI configuration cycle (rd or wr) succeeded, by
+	 * checking the status bits for errors like master or target abort.
+	 */
+	intr = preg->if_status;
+
+	len += sprintf(page + len, "PMC MSP PCI: After Cfg Wr\n");
+
+	/* Handle STDOUT calculations */
+	if (len <= off+count)
+		*eof = 1;
+	*start = page + off;
+	len -= off;
+	if (len > count)
+		len = count;
+	if (len < 0)
+		len = 0;
+
+	return len;
+}
+
+/*****************************************************************************
+ *
+ *  FUNCTION: pci_proc_init
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Create entries in the /proc filesystem for debug access.
+ *
+ *  INPUTS:      none
+ *
+ *  OUTPUTS:     none
+ *
+ *  RETURNS:     none
+ *
+ ****************************************************************************/
+static void pci_proc_init(void)
+{
+	create_proc_read_entry("pmc_msp_pci_rd_cnt", 0, NULL,
+				read_msp_pci_counts, NULL);
+	create_proc_read_entry("pmc_msp_pci_cfg_wr", 0, NULL,
+				gen_pci_cfg_wr, NULL);
+}
+#endif /* CONFIG_PROC_FS && PCI_COUNTERS */
+
+spinlock_t bpci_lock = SPIN_LOCK_UNLOCKED;
+
+/*****************************************************************************
+ *
+ *  STRUCT: pci_io_resource
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Defines the address range that pciauto() will use to
+ *               assign to the I/O BARs of PCI devices.
+ *
+ *               Use the start and end addresses of the MSP7120 PCI Host
+ *               Controller I/O space, in the form that they appear on the
+ *               PCI bus AFTER MSP7120 has performed address translation.
+ *
+ *               For I/O accesses, MSP7120 ignores OATRAN and maps I/O
+ *               accesses into the bottom 0xFFF region of address space,
+ *               so that is the range to put into the pci_io_resource
+ *               struct.
+ *
+ *               In MSP4200, the start address was 0x04 instead of the
+ * 		 expected 0x00. Will just assume there was a good reason
+ * 		 for this!
+ *
+ *  NOTES:       Linux, by default, will assign I/O space to the lowest
+ *               region of address space. Since MSP7120 and Linux,
+ *               by default, have no offset in between how they map, the
+ *               io_offset element of pci_controller struct should be set
+ *               to zero.
+ *  ELEMENTS:
+ *    name       - String used for a meaningful name.
+ *
+ *    start      - Start address of MSP7120's I/O space, as MSP7120 presents
+ *                 the address on the PCI bus.
+ *
+ *    end        - End address of MSP7120's I/O space, as MSP7120 presents
+ *                 the address on the PCI bus.
+ *
+ *    flags      - Attributes indicating the type of resource. In this case,
+ *                 indicate I/O space.
+ *
+ ****************************************************************************/
+static struct resource pci_io_resource = {
+	.name	= "pci IO space",
+	.start	= 0x04,
+	.end	= 0x0FFF,
+	.flags	= IORESOURCE_IO	/* I/O space */
+};
+
+/*****************************************************************************
+ *
+ *  STRUCT: pci_mem_resource
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Defines the address range that pciauto() will use to
+ *               assign to the memory BARs of PCI devices.
+ *
+ *               The .start and .end values are dependent upon how address
+ *               translation is performed by the OATRAN regiser.
+ *
+ *               The values to use for .start and .end are the values
+ *               in the form they appear on the PCI bus AFTER MSP7120 has
+ *               performed OATRAN address translation.
+ *
+ *  ELEMENTS:
+ *    name       - String used for a meaningful name.
+ *
+ *    start      - Start address of MSP7120's memory space, as MSP7120 presents
+ *                 the address on the PCI bus.
+ *
+ *    end        - End address of MSP7120's memory space, as MSP7120 presents
+ *                 the address on the PCI bus.
+ *
+ *    flags      - Attributes indicating the type of resource. In this case,
+ *                 indicate memory space.
+ *
+ ****************************************************************************/
+static struct resource pci_mem_resource = {
+	.name	= "pci memory space",
+	.start	= MSP_PCI_SPACE_BASE,
+	.end	= MSP_PCI_SPACE_END,
+	.flags	= IORESOURCE_MEM	 /* memory space */
+};
+
+/*****************************************************************************
+ *
+ *  FUNCTION: bpci_interrupt
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: PCI status interrupt handler. Updates the count of how
+ *               many times each status bit has been set, then clears
+ *               the status bits. If the appropriate macros are defined,
+ *               these counts can be viewed via the /proc filesystem.
+ *
+ *  INPUTS:      irq     - unused
+ *               dev_id  - unused
+ *               pt_regs - unused
+ *
+ *  OUTPUTS:     none
+ *
+ *  RETURNS:     PCIBIOS_SUCCESSFUL  - success
+ *
+ ****************************************************************************/
+static int bpci_interrupt(int irq, void *dev_id)
+{
+	struct msp_pci_regs *preg = (void *)PCI_BASE_REG;
+	unsigned int stat = preg->if_status;
+
+#if defined(CONFIG_PROC_FS) && defined(PCI_COUNTERS)
+	int i;
+	for (i = 0; i < 32; ++i) {
+		if ((1 << i) & stat)
+			++pci_int_count[i];
+	}
+#endif /* PROC_FS && PCI_COUNTERS */
+
+	/* printk("PCI ISR: Status=%08X\n", stat); */
+
+	/* write to clear all asserted interrupts */
+	preg->if_status = stat;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/*****************************************************************************
+ *
+ *  FUNCTION: msp_pcibios_config_access
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Performs a PCI configuration access (rd or wr), then
+ *               checks that the access succeeded by querying MSP7120's
+ *               PCI status bits.
+ *
+ *  INPUTS:
+ *               access_type  - kind of PCI configuration cycle to perform
+ *                              (read or write). Legal values are
+ *                              PCI_ACCESS_WRITE and PCI_ACCESS_READ.
+ *
+ *               bus          - pointer to the bus number of the device to
+ *                              be targetted for the configuration cycle.
+ *                              The only element of the pci_bus structure
+ *                              used is bus->number. This argument determines
+ *                              if the configuration access will be Type 0 or
+ *                              Type 1. Since MSP7120 assumes itself to be the
+ *                              PCI Host, any non-zero bus->number generates
+ *                              a Type 1 access.
+ *
+ *               devfn        - this is an 8-bit field. The lower three bits
+ *                              specify the function number of the device to
+ *                              be targetted for the configuration cycle, with
+ *                              all three-bit combinations being legal. The
+ *                              upper five bits specify the device number,
+ *                              with legal values being 10 to 31.
+ *
+ *               where        - address within the Configuration Header
+ *                              space to access.
+ *
+ *               data         - for write accesses, contains the data to
+ *                              write.
+ *
+ *  OUTPUTS:
+ *               data         - for read accesses, contains the value read.
+ *
+ *  RETURNS:     PCIBIOS_SUCCESSFUL  - success
+ *               -1                  - access failure
+ *
+ ****************************************************************************/
+int msp_pcibios_config_access(unsigned char access_type,
+				struct pci_bus *bus,
+				unsigned int devfn,
+				unsigned char where,
+				u32 *data)
+{
+	struct msp_pci_regs *preg = (void *)PCI_BASE_REG;
+	unsigned char bus_num = bus->number;
+	unsigned char dev_fn = (unsigned char)devfn;
+	unsigned long flags;
+	unsigned long intr;
+	unsigned long value;
+	static char pciirqflag;
+#if defined(CONFIG_PMC_MSP7120_GW) || defined(CONFIG_PMC_MSP7120_EVAL)
+	unsigned int	vpe_status;
+#endif
+
+#if defined(CONFIG_PROC_FS) && defined(PCI_COUNTERS)
+	if (proc_init == 0) {
+		pci_proc_init();
+		proc_init = ~0;
+	}
+#endif /* CONFIG_PROC_FS && PCI_COUNTERS */
+
+	/*
+	 * Just the first time this function invokes, allocate
+	 * an interrupt line for PCI host status interrupts. The
+	 * allocation assigns an interrupt handler to the interrupt.
+	 */
+	if (pciirqflag == 0) {
+		request_irq(MSP_INT_PCI,/* Hardcoded internal MSP7120 wiring */
+				bpci_interrupt,
+				SA_SHIRQ | SA_INTERRUPT,
+				"PMC MSP PCI Host",
+				preg);
+		pciirqflag = ~0;
+	}
+
+#if defined(CONFIG_PMC_MSP7120_GW) || defined(CONFIG_PMC_MSP7120_EVAL)
+	local_irq_save(flags);
+	vpe_status = dvpe();
+#else
+	spin_lock_irqsave(&bpci_lock, flags);
+#endif
+
+	/*
+	 * Clear PCI cause register bits.
+	 *
+	 * In Polo, the PCI Host had a dedicated DMA called the
+	 * Block Copy (not to be confused with the general purpose Block
+	 * Copy Engine block). There appear to have been special interrupts
+	 * for this Block Copy, called Block Copy 0 Fault (BC0F) and
+	 * Block Copy 1 Fault (BC1F). MSP4200 and MSP7120 don't have this
+	 * dedicated Block Copy block, so these two interrupts are now
+	 * marked reserved. In case the  Block Copy is resurrected in a
+	 * future design, maintain the code that treats these two interrupts
+	 * specially.
+	 *
+	 * Write to clear all interrupts in the PCI status register, aside
+	 * from BC0F and BC1F.
+	 */
+	preg->if_status = ~(BPCI_IFSTATUS_BC0F | BPCI_IFSTATUS_BC1F);
+
+	/* Setup address that is to appear on PCI bus */
+	preg->config_addr = BPCI_CFGADDR_ENABLE	|
+		(bus_num << BPCI_CFGADDR_BUSNUM_SHF) |
+		(dev_fn << BPCI_CFGADDR_FUNCTNUM_SHF) |
+		(where & 0xFC);
+
+	/* IF access is a PCI configuration write */
+	if (access_type == PCI_ACCESS_WRITE) {
+		value = cpu_to_le32(*data);
+		*PCI_CONFIG_SPACE_REG = value;
+	} else {
+		/* ELSE access is a PCI configuration read */
+		value = le32_to_cpu(*PCI_CONFIG_SPACE_REG);
+		*data = value;
+	}
+
+	/*
+	 * Check if the PCI configuration cycle (rd or wr) succeeded, by
+	 * checking the status bits for errors like master or target abort.
+	 */
+	intr = preg->if_status;
+
+	/* Clear config access */
+	preg->config_addr = 0;
+
+	/* IF error occurred */
+	if (intr & ~(BPCI_IFSTATUS_BC0F | BPCI_IFSTATUS_BC1F)) {
+		/* Clear status bits */
+		preg->if_status = ~(BPCI_IFSTATUS_BC0F | BPCI_IFSTATUS_BC1F);
+
+#if defined(CONFIG_PMC_MSP7120_GW) || defined(CONFIG_PMC_MSP7120_EVAL)
+		evpe(vpe_status);
+		local_irq_restore(flags);
+#else
+		spin_unlock_irqrestore(&bpci_lock, flags);
+#endif
+
+		return -1;
+	}
+
+#if defined(CONFIG_PMC_MSP7120_GW) || defined(CONFIG_PMC_MSP7120_EVAL)
+	evpe(vpe_status);
+	local_irq_restore(flags);
+#else
+	spin_unlock_irqrestore(&bpci_lock, flags);
+#endif
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/*****************************************************************************
+ *
+ *  FUNCTION: msp_pcibios_read_config_byte
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Read a byte from PCI configuration address spac
+ *               Since the hardware can't address 8 bit chunks
+ *               directly, read a 32-bit chunk, then mask off extraneous
+ *               bits.
+ *
+ *  INPUTS       bus    - structure containing attributes for the PCI bus
+ *                        that the read is destined for.
+ *               devfn  - device/function combination that the read is
+ *                        destined for.
+ *               where  - register within the Configuration Header space
+ *                        to access.
+ *
+ *  OUTPUTS      val    - read data
+ *
+ *  RETURNS:     PCIBIOS_SUCCESSFUL  - success
+ *               -1                  - read access failure
+ *
+ ****************************************************************************/
+static int
+msp_pcibios_read_config_byte(struct pci_bus *bus,
+				unsigned int devfn,
+				int where,
+				u32 *val)
+{
+	u32 data = 0;
+
+	/*
+	 * If the config access did not complete normally (e.g., underwent
+	 * master abort) do the PCI compliant thing, which is to supply an
+	 * all ones value.
+	 */
+	if (msp_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
+					where, &data)) {
+		*val = 0xFFFFFFFF;
+		return -1;
+	}
+
+	*val = (data >> ((where & 3) << 3)) & 0x0ff;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/*****************************************************************************
+ *
+ *  FUNCTION: msp_pcibios_read_config_word
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Read a word (16 bits) from PCI configuration address space.
+ *               Since the hardware can't address 16 bit chunks
+ *               directly, read a 32-bit chunk, then mask off extraneous
+ *               bits.
+ *
+ *  INPUTS       bus    - structure containing attributes for the PCI bus
+ *                        that the read is destined for.
+ *               devfn  - device/function combination that the read is
+ *                        destined for.
+ *               where  - register within the Configuration Header space
+ *                        to access.
+ *
+ *  OUTPUTS      val    - read data
+ *
+ *  RETURNS:     PCIBIOS_SUCCESSFUL           - success
+ *               PCIBIOS_BAD_REGISTER_NUMBER  - bad register address
+ *               -1                           - read access failure
+ *
+ ****************************************************************************/
+static int
+msp_pcibios_read_config_word(struct pci_bus *bus,
+				unsigned int devfn,
+				int where,
+				u32 *val)
+{
+	u32 data = 0;
+
+	/* if (where & 1) */	/* Commented out non-compliant code.
+				 * Should allow word access to configuration
+				 * registers, with only exception being when
+				 * the word access would wrap around into
+				 * the next dword.
+				 */
+	if ((where & 3) == 3) {
+		*val = 0xFFFFFFFF;
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+	}
+
+	/*
+	 * If the config access did not complete normally (e.g., underwent
+	 * master abort) do the PCI compliant thing, which is to supply an
+	 * all ones value.
+	 */
+	if (msp_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
+					where, &data)) {
+		*val = 0xFFFFFFFF;
+		return -1;
+	}
+
+	*val = (data >> ((where & 3) << 3)) & 0x0ffff;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/*****************************************************************************
+ *
+ *  FUNCTION: msp_pcibios_read_config_dword
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Read a double word (32 bits) from PCI configuration
+ *               address space.
+ *
+ *  INPUTS       bus    - structure containing attributes for the PCI bus
+ *                        that the read is destined for.
+ *               devfn  - device/function combination that the read is
+ *                        destined for.
+ *               where  - register within the Configuration Header space
+ *                        to access.
+ *
+ *  OUTPUTS      val    - read data
+ *
+ *  RETURNS:     PCIBIOS_SUCCESSFUL           - success
+ *               PCIBIOS_BAD_REGISTER_NUMBER  - bad register address
+ *               -1                           - read access failure
+ *
+ ****************************************************************************/
+static int
+msp_pcibios_read_config_dword(struct pci_bus *bus,
+				unsigned int devfn,
+				int where,
+				u32 *val)
+{
+	u32 data = 0;
+
+	/* Address must be dword aligned. */
+	if (where & 3) {
+		*val = 0xFFFFFFFF;
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+	}
+
+	/*
+	 * If the config access did not complete normally (e.g., underwent
+	 * master abort) do the PCI compliant thing, which is to supply an
+	 * all ones value.
+	 */
+	if (msp_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
+					where, &data)) {
+		*val = 0xFFFFFFFF;
+		return -1;
+	}
+
+	*val = data;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/*****************************************************************************
+ *
+ *  FUNCTION: msp_pcibios_write_config_byte
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Write a byte to PCI configuration address space.
+ *               Since the hardware can't address 8 bit chunks
+ *               directly, a read-modify-write is performed.
+ *
+ *  INPUTS       bus    - structure containing attributes for the PCI bus
+ *                        that the write is destined for.
+ *               devfn  - device/function combination that the write is
+ *                        destined for.
+ *               where  - register within the Configuration Header space
+ *                        to access.
+ *               val    - value to write
+ *
+ *  OUTPUTS      none
+ *
+ *  RETURNS:     PCIBIOS_SUCCESSFUL  - success
+ *               -1                  - write access failure
+ *
+ ****************************************************************************/
+static int
+msp_pcibios_write_config_byte(struct pci_bus *bus,
+				unsigned int devfn,
+				int where,
+				u8 val)
+{
+	u32 data = 0;
+
+	/* read config space */
+	if (msp_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
+					where, &data))
+		return -1;
+
+	/* modify the byte within the dword */
+	data = (data & ~(0xff << ((where & 3) << 3))) |
+			(val << ((where & 3) << 3));
+
+	/* write back the full dword */
+	if (msp_pcibios_config_access(PCI_ACCESS_WRITE, bus, devfn,
+					where, &data))
+		return -1;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/*****************************************************************************
+ *
+ *  FUNCTION: msp_pcibios_write_config_word
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Write a word (16-bits) to PCI configuration address space.
+ *               Since the hardware can't address 16 bit chunks
+ *               directly, a read-modify-write is performed.
+ *
+ *  INPUTS       bus    - structure containing attributes for the PCI bus
+ *                        that the write is destined for.
+ *               devfn  - device/function combination that the write is
+ *                        destined for.
+ *               where  - register within the Configuration Header space
+ *                        to access.
+ *               val    - value to write
+ *
+ *  OUTPUTS      none
+ *
+ *  RETURNS:     PCIBIOS_SUCCESSFUL           - success
+ *               PCIBIOS_BAD_REGISTER_NUMBER  - bad register address
+ *               -1                           - write access failure
+ *
+ ****************************************************************************/
+static int
+msp_pcibios_write_config_word(struct pci_bus *bus,
+				unsigned int devfn,
+				int where,
+				u16 val)
+{
+	u32 data = 0;
+
+	/* Fixed non-compliance: if (where & 1) */
+	if ((where & 3) == 3)
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+
+	/* read config space */
+	if (msp_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
+					where, &data))
+		return -1;
+
+	/* modify the word within the dword */
+	data = (data & ~(0xffff << ((where & 3) << 3))) |
+			(val << ((where & 3) << 3));
+
+	/* write back the full dword */
+	if (msp_pcibios_config_access(PCI_ACCESS_WRITE, bus, devfn,
+					where, &data))
+		return -1;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/*****************************************************************************
+ *
+ *  FUNCTION: msp_pcibios_write_config_dword
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Write a double word (32-bits) to PCI configuration address
+ *               space.
+ *
+ *  INPUTS       bus    - structure containing attributes for the PCI bus
+ *                        that the write is destined for.
+ *               devfn  - device/function combination that the write is
+ *                        destined for.
+ *               where  - register within the Configuration Header space
+ *                        to access.
+ *               val    - value to write
+ *
+ *  OUTPUTS      none
+ *
+ *  RETURNS:     PCIBIOS_SUCCESSFUL           - success
+ *               PCIBIOS_BAD_REGISTER_NUMBER  - bad register address
+ *               -1                           - write access failure
+ *
+ ****************************************************************************/
+static int
+msp_pcibios_write_config_dword(struct pci_bus *bus,
+				unsigned int devfn,
+				int where,
+				u32 val)
+{
+	/* check that address is dword aligned */
+	if (where & 3)
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+
+	/* perform write */
+	if (msp_pcibios_config_access(PCI_ACCESS_WRITE, bus, devfn,
+					where, &val))
+		return -1;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/*****************************************************************************
+ *
+ *  FUNCTION: msp_pcibios_read_config
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Interface the PCI configuration read request with
+ *               the appropriate function, based on how many bytes
+ *               the read request is.
+ *
+ *  INPUTS       bus    - structure containing attributes for the PCI bus
+ *                        that the write is destined for.
+ *               devfn  - device/function combination that the write is
+ *                        destined for.
+ *               where  - register within the Configuration Header space
+ *                        to access.
+ *               size   - in units of bytes, should be 1, 2, or 4.
+ *
+ *  OUTPUTS      val    - value read, with any extraneous bytes masked
+ *                        to zero.
+ *
+ *  RETURNS:     PCIBIOS_SUCCESSFUL   - success
+ *               -1                   - failure
+ *
+ ****************************************************************************/
+int
+msp_pcibios_read_config(struct pci_bus *bus,
+			unsigned int	devfn,
+			int where,
+			int size,
+			u32 *val)
+{
+	if (size == 1) {
+		if (msp_pcibios_read_config_byte(bus, devfn, where, val)) {
+			return -1;
+		}
+	} else if (size == 2) {
+		if (msp_pcibios_read_config_word(bus, devfn, where, val)) {
+			return -1;
+		}
+	} else if (size == 4) {
+		if (msp_pcibios_read_config_dword(bus, devfn, where, val)) {
+			return -1;
+		}
+	} else {
+		*val = 0xFFFFFFFF;
+		return -1;
+	}
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/*****************************************************************************
+ *
+ *  FUNCTION: msp_pcibios_write_config
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Interface the PCI configuration write request with
+ *               the appropriate function, based on how many bytes
+ *               the read request is.
+ *
+ *  INPUTS       bus    - structure containing attributes for the PCI bus
+ *                        that the write is destined for.
+ *               devfn  - device/function combination that the write is
+ *                        destined for.
+ *               where  - register within the Configuration Header space
+ *                        to access.
+ *               size   - in units of bytes, should be 1, 2, or 4.
+ *               val    - value to write
+ *
+ *  OUTPUTS:     none
+ *
+ *  RETURNS:     PCIBIOS_SUCCESSFUL   - success
+ *               -1                   - failure
+ *
+ ****************************************************************************/
+int
+msp_pcibios_write_config(struct pci_bus *bus,
+			unsigned int devfn,
+			int where,
+			int size,
+			u32 val)
+{
+	if (size == 1) {
+		if (msp_pcibios_write_config_byte(bus, devfn,
+						where, (u8)(0xFF & val))) {
+			return -1;
+		}
+	} else if (size == 2) {
+		if (msp_pcibios_write_config_word(bus, devfn,
+						where, (u16)(0xFFFF & val))) {
+			return -1;
+		}
+	} else if (size == 4) {
+		if (msp_pcibios_write_config_dword(bus, devfn, where, val)) {
+			return -1;
+		}
+	} else {
+		return -1;
+	}
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/*****************************************************************************
+ *
+ *  STRUCTURE: msp_pci_ops
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: structure to abstract the hardware specific PCI
+ *               configuration accesses.
+ *
+ *  ELEMENTS:
+ *    read      - function for Linux to generate PCI Configuration reads.
+ *    write     - function for Linux to generate PCI Configuration writes.
+ *
+ ****************************************************************************/
+struct pci_ops msp_pci_ops = {
+	.read = msp_pcibios_read_config,
+	.write = msp_pcibios_write_config
+};
+
+/*****************************************************************************
+ *
+ *  STRUCTURE: msp_pci_controller
+ *  _________________________________________________________________________
+ *
+ *  Describes the attributes of the MSP7120 PCI Host Controller
+ *
+ *  ELEMENTS:
+ *    pci_ops      - abstracts the hardware specific PCI configuration
+ *                   accesses.
+ *
+ *    mem_resource - address range pciauto() uses to assign to PCI device
+ *                   memory BARs.
+ *
+ *    mem_offset   - offset between how MSP7120 outbound PCI memory
+ *                   transaction addresses appear on the PCI bus and how Linux
+ *                   wants to configure memory BARs of the PCI devices.
+ *                   MSP7120 does nothing funky, so just set to zero.
+ *
+ *    io_resource  - address range pciauto() uses to assign to PCI device
+ *                   I/O BARs.
+ *
+ *    io_offset    - offset between how MSP7120 outbound PCI I/O
+ *                   transaction addresses appear on the PCI bus and how
+ *                   Linux defaults to configure I/O BARs of the PCI devices.
+ *                   MSP7120 maps outbound I/O accesses into the bottom
+ *                   bottom 4K of PCI address space (and ignores OATRAN).
+ *                   Since the Linux default is to configure I/O BARs to the
+ *                   bottom 4K, no special offset is needed. Just set to zero.
+ *
+ ****************************************************************************/
+static struct pci_controller msp_pci_controller = {
+	.pci_ops	= &msp_pci_ops,
+	.mem_resource	= &pci_mem_resource,
+	.mem_offset	= 0,
+	.io_resource	= &pci_io_resource,
+	.io_offset	= 0
+};
+
+/*****************************************************************************
+ *
+ *  FUNCTION: msp_pci_init
+ *  _________________________________________________________________________
+ *
+ *  DESCRIPTION: Initialize the PCI Host Controller and register it with
+ *               Linux so Linux can seize control of the PCI bus.
+ *
+ ****************************************************************************/
+void __init msp_pci_init(void)
+{
+	struct msp_pci_regs *preg = (void *)PCI_BASE_REG;
+	u32 id;
+
+	/* Extract Device ID */
+	id = read_reg32(PCI_JTAG_DEVID_REG, 0xFFFF) >> 12;
+
+	/* Check if JTAG ID identifies MSP7120 */
+	if (!MSP_HAS_PCI(id)) {
+		printk(KERN_WARNING "PCI: No PCI; id reads as %x\n", id);
+		goto no_pci;
+	}
+
+	/*
+	 * Enable flushing of the PCI-SDRAM queue upon a read
+	 * of the SDRAM's Memory Configuration Register.
+	 */
+	*(unsigned long *)QFLUSH_REG_1 = 3;
+
+	/* Configure PCI Host Controller. */
+	preg->if_status	= ~0;		/* Clear cause register bits */
+	preg->config_addr = 0;		/* Clear config access */
+	preg->oatran	= MSP_PCI_OATRAN; /* PCI outbound addr translation */
+	preg->if_mask	= 0xF8BF87C0;	/* Enable all PCI status interrupts */
+
+	/* configure so inb(), outb(), and family are functional */
+	set_io_port_base(MSP_PCI_IOSPACE_BASE);
+
+	/* Tell Linux the details of the MSP7120 PCI Host Controller */
+	register_pci_controller(&msp_pci_controller);
+
+	return;
+
+no_pci:
+	/* Disable PCI channel */
+	printk(KERN_WARNING "PCI: no host PCI bus detected\n");
+}