diff options
Diffstat (limited to 'drivers/mtd/maps/intel_vr_nor.c')
-rw-r--r-- | drivers/mtd/maps/intel_vr_nor.c | 265 |
1 files changed, 265 insertions, 0 deletions
diff --git a/drivers/mtd/maps/intel_vr_nor.c b/drivers/mtd/maps/intel_vr_nor.c new file mode 100644 index 000000000..d67b845b0 --- /dev/null +++ b/drivers/mtd/maps/intel_vr_nor.c @@ -0,0 +1,265 @@ +/* + * 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_register(p->info, 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->dev.parent = &p->dev->dev; + + 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(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(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 const 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); |