ops-pmcmsp.c

linux 内核源代码

/*
 * PMC-Sierra MSP board specific pci_ops
 *
 * Copyright 2001 MontaVista Software Inc.
 * Copyright 2005-2007 PMC-Sierra, Inc
 *
 * Author: Jun Sun, [e-mail] or [e-mail]
 *
 * Much of the code is derived from the original DDB5074 port by
 * Geert Uytterhoeven <[e-mail]>
 *
 * 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 */

DEFINE_SPINLOCK(bpci_lock);

/*****************************************************************************
 *
 *  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;
}

/*****************************************************************************