diff options
Diffstat (limited to 'arch/sh/drivers/pci/ops-dreamcast.c')
-rw-r--r-- | arch/sh/drivers/pci/ops-dreamcast.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/arch/sh/drivers/pci/ops-dreamcast.c b/arch/sh/drivers/pci/ops-dreamcast.c new file mode 100644 index 000000000..16e0a1baa --- /dev/null +++ b/arch/sh/drivers/pci/ops-dreamcast.c @@ -0,0 +1,82 @@ +/* + * PCI operations for the Sega Dreamcast + * + * Copyright (C) 2001, 2002 M. R. Brown + * Copyright (C) 2002, 2003 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/sched.h> +#include <linux/kernel.h> +#include <linux/param.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/irq.h> +#include <linux/pci.h> +#include <linux/module.h> +#include <linux/io.h> +#include <mach/pci.h> + +/* + * The !gapspci_config_access case really shouldn't happen, ever, unless + * someone implicitly messes around with the last devfn value.. otherwise we + * only support a single device anyways, and if we didn't have a BBA, we + * wouldn't make it terribly far through the PCI setup anyways. + * + * Also, we could very easily support both Type 0 and Type 1 configurations + * here, but since it doesn't seem that there is any such implementation in + * existence, we don't bother. + * + * I suppose if someone actually gets around to ripping the chip out of + * the BBA and hanging some more devices off of it, then this might be + * something to take into consideration. However, due to the cost of the BBA, + * and the general lack of activity by DC hardware hackers, this doesn't seem + * likely to happen anytime soon. + */ +static int gapspci_config_access(unsigned char bus, unsigned int devfn) +{ + return (bus == 0) && (devfn == 0); +} + +/* + * We can also actually read and write in b/w/l sizes! Thankfully this part + * was at least done right, and we don't have to do the stupid masking and + * shifting that we do on the 7751! Small wonders never cease to amaze. + */ +static int gapspci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val) +{ + *val = 0xffffffff; + + if (!gapspci_config_access(bus->number, devfn)) + return PCIBIOS_DEVICE_NOT_FOUND; + + switch (size) { + case 1: *val = inb(GAPSPCI_BBA_CONFIG+where); break; + case 2: *val = inw(GAPSPCI_BBA_CONFIG+where); break; + case 4: *val = inl(GAPSPCI_BBA_CONFIG+where); break; + } + + return PCIBIOS_SUCCESSFUL; +} + +static int gapspci_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 val) +{ + if (!gapspci_config_access(bus->number, devfn)) + return PCIBIOS_DEVICE_NOT_FOUND; + + switch (size) { + case 1: outb(( u8)val, GAPSPCI_BBA_CONFIG+where); break; + case 2: outw((u16)val, GAPSPCI_BBA_CONFIG+where); break; + case 4: outl((u32)val, GAPSPCI_BBA_CONFIG+where); break; + } + + return PCIBIOS_SUCCESSFUL; +} + +struct pci_ops gapspci_pci_ops = { + .read = gapspci_read, + .write = gapspci_write, +}; |