drivers/mtd/maps/intel_vr_nor.c - kernel/bruno - Git at Google

 /*
  * drivers/mtd/maps/intel_vr_nor.c
  *
  * An MTD map driver for a NOR flash bank on the Expansion Bus of the Intel
  * Vermilion Range chipset.
  *
  * The Vermilion Range Expansion Bus supports four chip selects, each of which
  * has 64MiB of address space.  The 2nd BAR of the Expansion Bus PCI Device
  * is a 256MiB memory region containing the address spaces for all four of the
  * chip selects, with start addresses hardcoded on 64MiB boundaries.
  *
  * This map driver only supports NOR flash on chip select 0.  The buswidth
  * (either 8 bits or 16 bits) is determined by reading the Expansion Bus Timing
  * and Control Register for Chip Select 0 (EXP_TIMING_CS0).  This driver does
  * not modify the value in the EXP_TIMING_CS0 register except to enable writing
  * and disable boot acceleration.  The timing parameters in the register are
  * assumed to have been properly initialized by the BIOS.  The reset default
  * timing parameters are maximally conservative (slow), so access to the flash
  * will be slower than it should be if the BIOS has not initialized the timing
  * parameters.
  *
  * Author: Andy Lowe <alowe@mvista.com>
  *
  * 2006 (c) MontaVista Software, Inc. This file is licensed under
  * the terms of the GNU General Public License version 2. This program
  * is licensed "as is" without any warranty of any kind, whether express
  * or implied.
  */

 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/pci.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/map.h>
 #include <linux/mtd/partitions.h>
 #include <linux/mtd/cfi.h>
 #include <linux/mtd/flashchip.h>

 #define DRV_NAME "vr_nor"

 struct vr_nor_mtd {
 	void __iomem *csr_base;
 	struct map_info map;
 	struct mtd_info *info;
 	struct pci_dev *dev;
 };

 /* Expansion Bus Configuration and Status Registers are in BAR 0 */
 #define EXP_CSR_MBAR 0
 /* Expansion Bus Memory Window is BAR 1 */
 #define EXP_WIN_MBAR 1
 /* Maximum address space for Chip Select 0 is 64MiB */
 #define CS0_SIZE 0x04000000
 /* Chip Select 0 is at offset 0 in the Memory Window */
 #define CS0_START 0x0
 /* Chip Select 0 Timing Register is at offset 0 in CSR */
 #define EXP_TIMING_CS0 0x00
 #define TIMING_CS_EN		(1 << 31)	/* Chip Select Enable */
 #define TIMING_BOOT_ACCEL_DIS	(1 <<  8)	/* Boot Acceleration Disable */
 #define TIMING_WR_EN		(1 <<  1)	/* Write Enable */
 #define TIMING_BYTE_EN		(1 <<  0)	/* 8-bit vs 16-bit bus */
 #define TIMING_MASK		0x3FFF0000

 static void vr_nor_destroy_partitions(struct vr_nor_mtd *p)
 {
 	mtd_device_unregister(p->info);
 }

 static int vr_nor_init_partitions(struct vr_nor_mtd *p)
 {
 	/* register the flash bank */
 	/* partition the flash bank */
 	return mtd_device_parse_register(p->info, NULL, NULL, NULL, 0);
 }

 static void vr_nor_destroy_mtd_setup(struct vr_nor_mtd *p)
 {
 	map_destroy(p->info);
 }

 static int vr_nor_mtd_setup(struct vr_nor_mtd *p)
 {
 	static const char * const probe_types[] =
 	    { "cfi_probe", "jedec_probe", NULL };
 	const char * const *type;

 	for (type = probe_types; !p->info && *type; type++)
 		p->info = do_map_probe(*type, &p->map);
 	if (!p->info)
 		return -ENODEV;

 	p->info->owner = THIS_MODULE;

 	return 0;
 }

 static void vr_nor_destroy_maps(struct vr_nor_mtd *p)
 {
 	unsigned int exp_timing_cs0;

 	/* write-protect the flash bank */
 	exp_timing_cs0 = readl(p->csr_base + EXP_TIMING_CS0);
 	exp_timing_cs0 &= ~TIMING_WR_EN;
 	writel(exp_timing_cs0, p->csr_base + EXP_TIMING_CS0);

 	/* unmap the flash window */
 	iounmap(p->map.virt);

 	/* unmap the csr window */
 	iounmap(p->csr_base);
 }

 /*
  * Initialize the map_info structure and map the flash.
  * Returns 0 on success, nonzero otherwise.
  */
 static int vr_nor_init_maps(struct vr_nor_mtd *p)
 {
 	unsigned long csr_phys, csr_len;
 	unsigned long win_phys, win_len;
 	unsigned int exp_timing_cs0;
 	int err;

 	csr_phys = pci_resource_start(p->dev, EXP_CSR_MBAR);
 	csr_len = pci_resource_len(p->dev, EXP_CSR_MBAR);
 	win_phys = pci_resource_start(p->dev, EXP_WIN_MBAR);
 	win_len = pci_resource_len(p->dev, EXP_WIN_MBAR);

 	if (!csr_phys || !csr_len || !win_phys || !win_len)
 		return -ENODEV;

 	if (win_len < (CS0_START + CS0_SIZE))
 		return -ENXIO;

 	p->csr_base = ioremap_nocache(csr_phys, csr_len);
 	if (!p->csr_base)
 		return -ENOMEM;

 	exp_timing_cs0 = readl(p->csr_base + EXP_TIMING_CS0);
 	if (!(exp_timing_cs0 & TIMING_CS_EN)) {
 		dev_warn(&p->dev->dev, "Expansion Bus Chip Select 0 "
 		       "is disabled.\n");
 		err = -ENODEV;
 		goto release;
 	}
 	if ((exp_timing_cs0 & TIMING_MASK) == TIMING_MASK) {
 		dev_warn(&p->dev->dev, "Expansion Bus Chip Select 0 "
 		       "is configured for maximally slow access times.\n");
 	}
 	p->map.name = DRV_NAME;
 	p->map.bankwidth = (exp_timing_cs0 & TIMING_BYTE_EN) ? 1 : 2;
 	p->map.phys = win_phys + CS0_START;
 	p->map.size = CS0_SIZE;
 	p->map.virt = ioremap_nocache(p->map.phys, p->map.size);
 	if (!p->map.virt) {
 		err = -ENOMEM;
 		goto release;
 	}
 	simple_map_init(&p->map);

 	/* Enable writes to flash bank */
 	exp_timing_cs0 |= TIMING_BOOT_ACCEL_DIS | TIMING_WR_EN;
 	writel(exp_timing_cs0, p->csr_base + EXP_TIMING_CS0);

 	return 0;

       release:
 	iounmap(p->csr_base);
 	return err;
 }

 static struct pci_device_id vr_nor_pci_ids[] = {
 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x500D)},
 	{0,}
 };

 static void vr_nor_pci_remove(struct pci_dev *dev)
 {
 	struct vr_nor_mtd *p = pci_get_drvdata(dev);

 	vr_nor_destroy_partitions(p);
 	vr_nor_destroy_mtd_setup(p);
 	vr_nor_destroy_maps(p);
 	kfree(p);
 	pci_release_regions(dev);
 	pci_disable_device(dev);
 }

 static int vr_nor_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
 {
 	struct vr_nor_mtd *p = NULL;
 	unsigned int exp_timing_cs0;
 	int err;

 	err = pci_enable_device(dev);
 	if (err)
 		goto out;

 	err = pci_request_regions(dev, DRV_NAME);
 	if (err)
 		goto disable_dev;

 	p = kzalloc(sizeof(*p), GFP_KERNEL);
 	err = -ENOMEM;
 	if (!p)
 		goto release;

 	p->dev = dev;

 	err = vr_nor_init_maps(p);
 	if (err)
 		goto release;

 	err = vr_nor_mtd_setup(p);
 	if (err)
 		goto destroy_maps;

 	err = vr_nor_init_partitions(p);
 	if (err)
 		goto destroy_mtd_setup;

 	pci_set_drvdata(dev, p);

 	return 0;

       destroy_mtd_setup:
 	map_destroy(p->info);

       destroy_maps:
 	/* write-protect the flash bank */
 	exp_timing_cs0 = readl(p->csr_base + EXP_TIMING_CS0);
 	exp_timing_cs0 &= ~TIMING_WR_EN;
 	writel(exp_timing_cs0, p->csr_base + EXP_TIMING_CS0);

 	/* unmap the flash window */
 	iounmap(p->map.virt);

 	/* unmap the csr window */
 	iounmap(p->csr_base);

       release:
 	kfree(p);
 	pci_release_regions(dev);

       disable_dev:
 	pci_disable_device(dev);

       out:
 	return err;
 }

 static struct pci_driver vr_nor_pci_driver = {
 	.name = DRV_NAME,
 	.probe = vr_nor_pci_probe,
 	.remove = vr_nor_pci_remove,
 	.id_table = vr_nor_pci_ids,
 };

 module_pci_driver(vr_nor_pci_driver);

 MODULE_AUTHOR("Andy Lowe");
 MODULE_DESCRIPTION("MTD map driver for NOR flash on Intel Vermilion Range");
 MODULE_LICENSE("GPL");
 MODULE_DEVICE_TABLE(pci, vr_nor_pci_ids);
	/*
	* drivers/mtd/maps/intel_vr_nor.c
	*
	* An MTD map driver for a NOR flash bank on the Expansion Bus of the Intel
	* Vermilion Range chipset.
	*
	* The Vermilion Range Expansion Bus supports four chip selects, each of which
	* has 64MiB of address space. The 2nd BAR of the Expansion Bus PCI Device
	* is a 256MiB memory region containing the address spaces for all four of the
	* chip selects, with start addresses hardcoded on 64MiB boundaries.
	*
	* This map driver only supports NOR flash on chip select 0. The buswidth
	* (either 8 bits or 16 bits) is determined by reading the Expansion Bus Timing
	* and Control Register for Chip Select 0 (EXP_TIMING_CS0). This driver does
	* not modify the value in the EXP_TIMING_CS0 register except to enable writing
	* and disable boot acceleration. The timing parameters in the register are
	* assumed to have been properly initialized by the BIOS. The reset default
	* timing parameters are maximally conservative (slow), so access to the flash
	* will be slower than it should be if the BIOS has not initialized the timing
	* parameters.
	*
	* Author: Andy Lowe <alowe@mvista.com>
	*
	* 2006 (c) MontaVista Software, Inc. This file is licensed under
	* the terms of the GNU General Public License version 2. This program
	* is licensed "as is" without any warranty of any kind, whether express
	* or implied.
	*/

	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/slab.h>
	#include <linux/pci.h>
	#include <linux/mtd/mtd.h>
	#include <linux/mtd/map.h>
	#include <linux/mtd/partitions.h>
	#include <linux/mtd/cfi.h>
	#include <linux/mtd/flashchip.h>

	#define DRV_NAME "vr_nor"

	struct vr_nor_mtd {
	void __iomem *csr_base;
	struct map_info map;
	struct mtd_info *info;
	struct pci_dev *dev;
	};

	/* Expansion Bus Configuration and Status Registers are in BAR 0 */
	#define EXP_CSR_MBAR 0
	/* Expansion Bus Memory Window is BAR 1 */
	#define EXP_WIN_MBAR 1
	/* Maximum address space for Chip Select 0 is 64MiB */
	#define CS0_SIZE 0x04000000
	/* Chip Select 0 is at offset 0 in the Memory Window */
	#define CS0_START 0x0
	/* Chip Select 0 Timing Register is at offset 0 in CSR */
	#define EXP_TIMING_CS0 0x00
	#define TIMING_CS_EN (1 << 31) /* Chip Select Enable */
	#define TIMING_BOOT_ACCEL_DIS (1 << 8) /* Boot Acceleration Disable */
	#define TIMING_WR_EN (1 << 1) /* Write Enable */
	#define TIMING_BYTE_EN (1 << 0) /* 8-bit vs 16-bit bus */
	#define TIMING_MASK 0x3FFF0000

	static void vr_nor_destroy_partitions(struct vr_nor_mtd *p)
	{
	mtd_device_unregister(p->info);
	}

	static int vr_nor_init_partitions(struct vr_nor_mtd *p)
	{
	/* register the flash bank */
	/* partition the flash bank */
	return mtd_device_parse_register(p->info, NULL, NULL, NULL, 0);
	}

	static void vr_nor_destroy_mtd_setup(struct vr_nor_mtd *p)
	{
	map_destroy(p->info);
	}

	static int vr_nor_mtd_setup(struct vr_nor_mtd *p)
	{
	static const char * const probe_types[] =
	{ "cfi_probe", "jedec_probe", NULL };
	const char * const *type;

	for (type = probe_types; !p->info && *type; type++)
	p->info = do_map_probe(*type, &p->map);
	if (!p->info)
	return -ENODEV;

	p->info->owner = THIS_MODULE;

	return 0;
	}

	static void vr_nor_destroy_maps(struct vr_nor_mtd *p)
	{
	unsigned int exp_timing_cs0;

	/* write-protect the flash bank */
	exp_timing_cs0 = readl(p->csr_base + EXP_TIMING_CS0);
	exp_timing_cs0 &= ~TIMING_WR_EN;
	writel(exp_timing_cs0, p->csr_base + EXP_TIMING_CS0);

	/* unmap the flash window */
	iounmap(p->map.virt);

	/* unmap the csr window */
	iounmap(p->csr_base);
	}

	/*
	* Initialize the map_info structure and map the flash.
	* Returns 0 on success, nonzero otherwise.
	*/
	static int vr_nor_init_maps(struct vr_nor_mtd *p)
	{
	unsigned long csr_phys, csr_len;
	unsigned long win_phys, win_len;
	unsigned int exp_timing_cs0;
	int err;

	csr_phys = pci_resource_start(p->dev, EXP_CSR_MBAR);
	csr_len = pci_resource_len(p->dev, EXP_CSR_MBAR);
	win_phys = pci_resource_start(p->dev, EXP_WIN_MBAR);
	win_len = pci_resource_len(p->dev, EXP_WIN_MBAR);

	if (!csr_phys \|\| !csr_len \|\| !win_phys \|\| !win_len)
	return -ENODEV;

	if (win_len < (CS0_START + CS0_SIZE))
	return -ENXIO;

	p->csr_base = ioremap_nocache(csr_phys, csr_len);
	if (!p->csr_base)
	return -ENOMEM;

	exp_timing_cs0 = readl(p->csr_base + EXP_TIMING_CS0);
	if (!(exp_timing_cs0 & TIMING_CS_EN)) {
	dev_warn(&p->dev->dev, "Expansion Bus Chip Select 0 "
	"is disabled.\n");
	err = -ENODEV;
	goto release;
	}
	if ((exp_timing_cs0 & TIMING_MASK) == TIMING_MASK) {
	dev_warn(&p->dev->dev, "Expansion Bus Chip Select 0 "
	"is configured for maximally slow access times.\n");
	}
	p->map.name = DRV_NAME;
	p->map.bankwidth = (exp_timing_cs0 & TIMING_BYTE_EN) ? 1 : 2;
	p->map.phys = win_phys + CS0_START;
	p->map.size = CS0_SIZE;
	p->map.virt = ioremap_nocache(p->map.phys, p->map.size);
	if (!p->map.virt) {
	err = -ENOMEM;
	goto release;
	}
	simple_map_init(&p->map);

	/* Enable writes to flash bank */
	exp_timing_cs0 \|= TIMING_BOOT_ACCEL_DIS \| TIMING_WR_EN;
	writel(exp_timing_cs0, p->csr_base + EXP_TIMING_CS0);

	return 0;

	release:
	iounmap(p->csr_base);
	return err;
	}

	static struct pci_device_id vr_nor_pci_ids[] = {
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x500D)},
	{0,}
	};

	static void vr_nor_pci_remove(struct pci_dev *dev)
	{
	struct vr_nor_mtd *p = pci_get_drvdata(dev);

	vr_nor_destroy_partitions(p);
	vr_nor_destroy_mtd_setup(p);
	vr_nor_destroy_maps(p);
	kfree(p);
	pci_release_regions(dev);
	pci_disable_device(dev);
	}

	static int vr_nor_pci_probe(struct pci_dev dev, const struct pci_device_id id)
	{
	struct vr_nor_mtd *p = NULL;
	unsigned int exp_timing_cs0;
	int err;

	err = pci_enable_device(dev);
	if (err)
	goto out;

	err = pci_request_regions(dev, DRV_NAME);
	if (err)
	goto disable_dev;

	p = kzalloc(sizeof(*p), GFP_KERNEL);
	err = -ENOMEM;
	if (!p)
	goto release;

	p->dev = dev;

	err = vr_nor_init_maps(p);
	if (err)
	goto release;

	err = vr_nor_mtd_setup(p);
	if (err)
	goto destroy_maps;

	err = vr_nor_init_partitions(p);
	if (err)
	goto destroy_mtd_setup;

	pci_set_drvdata(dev, p);

	return 0;

	destroy_mtd_setup:
	map_destroy(p->info);

	destroy_maps:
	/* write-protect the flash bank */
	exp_timing_cs0 = readl(p->csr_base + EXP_TIMING_CS0);
	exp_timing_cs0 &= ~TIMING_WR_EN;
	writel(exp_timing_cs0, p->csr_base + EXP_TIMING_CS0);

	/* unmap the flash window */
	iounmap(p->map.virt);

	/* unmap the csr window */
	iounmap(p->csr_base);

	release:
	kfree(p);
	pci_release_regions(dev);

	disable_dev:
	pci_disable_device(dev);

	out:
	return err;
	}

	static struct pci_driver vr_nor_pci_driver = {
	.name = DRV_NAME,
	.probe = vr_nor_pci_probe,
	.remove = vr_nor_pci_remove,
	.id_table = vr_nor_pci_ids,
	};

	module_pci_driver(vr_nor_pci_driver);

	MODULE_AUTHOR("Andy Lowe");
	MODULE_DESCRIPTION("MTD map driver for NOR flash on Intel Vermilion Range");
	MODULE_LICENSE("GPL");
	MODULE_DEVICE_TABLE(pci, vr_nor_pci_ids);