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Diffstat (limited to 'arch/m68k/platform/coldfire/pci.c')
| -rw-r--r-- | arch/m68k/platform/coldfire/pci.c | 327 | 
1 files changed, 327 insertions, 0 deletions
diff --git a/arch/m68k/platform/coldfire/pci.c b/arch/m68k/platform/coldfire/pci.c new file mode 100644 index 00000000000..553210d3d4c --- /dev/null +++ b/arch/m68k/platform/coldfire/pci.c @@ -0,0 +1,327 @@ +/* + * pci.c -- PCI bus support for ColdFire processors + * + * (C) Copyright 2012, Greg Ungerer <gerg@uclinux.com> + * + * 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/types.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/io.h> +#include <linux/pci.h> +#include <linux/delay.h> +#include <asm/coldfire.h> +#include <asm/mcfsim.h> +#include <asm/m54xxpci.h> + +/* + * Memory and IO mappings. We use a 1:1 mapping for local host memory to + * PCI bus memory (no reason not to really). IO space doesn't matter, we + * always use access functions for that. The device configuration space is + * mapped over the IO map space when we enable it in the PCICAR register. + */ +#define	PCI_MEM_PA	0xf0000000		/* Host physical address */ +#define	PCI_MEM_BA	0xf0000000		/* Bus physical address */ +#define	PCI_MEM_SIZE	0x08000000		/* 128 MB */ +#define	PCI_MEM_MASK	(PCI_MEM_SIZE - 1) + +#define	PCI_IO_PA	0xf8000000		/* Host physical address */ +#define	PCI_IO_BA	0x00000000		/* Bus physical address */ +#define	PCI_IO_SIZE	0x00010000		/* 64k */ +#define	PCI_IO_MASK	(PCI_IO_SIZE - 1) + +static struct pci_bus *rootbus; +static unsigned long iospace; + +/* + * We need to be carefull probing on bus 0 (directly connected to host + * bridge). We should only acccess the well defined possible devices in + * use, ignore aliases and the like. + */ +static unsigned char mcf_host_slot2sid[32] = { +	0, 0, 0, 0, 0, 0, 0, 0, +	0, 0, 0, 0, 0, 0, 0, 0, +	0, 1, 2, 0, 3, 4, 0, 0, +	0, 0, 0, 0, 0, 0, 0, 0, +}; + +static unsigned char mcf_host_irq[] = { +	0, 69, 69, 71, 71, +}; + + +static inline void syncio(void) +{ +	/* The ColdFire "nop" instruction waits for all bus IO to complete */ +	__asm__ __volatile__ ("nop"); +} + +/* + * Configuration space access functions. Configuration space access is + * through the IO mapping window, enabling it via the PCICAR register. + */ +static unsigned long mcf_mk_pcicar(int bus, unsigned int devfn, int where) +{ +	return (bus << PCICAR_BUSN) | (devfn << PCICAR_DEVFNN) | (where & 0xfc); +} + +static int mcf_pci_readconfig(struct pci_bus *bus, unsigned int devfn, +	int where, int size, u32 *value) +{ +	unsigned long addr; + +	*value = 0xffffffff; + +	if (bus->number == 0) { +		if (mcf_host_slot2sid[PCI_SLOT(devfn)] == 0) +			return PCIBIOS_SUCCESSFUL; +	} + +	syncio(); +	addr = mcf_mk_pcicar(bus->number, devfn, where); +	__raw_writel(PCICAR_E | addr, PCICAR); +	addr = iospace + (where & 0x3); + +	switch (size) { +	case 1: +		*value = __raw_readb(addr); +		break; +	case 2: +		*value = le16_to_cpu(__raw_readw(addr)); +		break; +	default: +		*value = le32_to_cpu(__raw_readl(addr)); +		break; +	} + +	syncio(); +	__raw_writel(0, PCICAR); +	return PCIBIOS_SUCCESSFUL; +} + +static int mcf_pci_writeconfig(struct pci_bus *bus, unsigned int devfn, +	int where, int size, u32 value) +{ +	unsigned long addr; + +	if (bus->number == 0) { +		if (mcf_host_slot2sid[PCI_SLOT(devfn)] == 0) +			return PCIBIOS_SUCCESSFUL; +	} + +	syncio(); +	addr = mcf_mk_pcicar(bus->number, devfn, where); +	__raw_writel(PCICAR_E | addr, PCICAR); +	addr = iospace + (where & 0x3); + +	switch (size) { +	case 1: +		 __raw_writeb(value, addr); +		break; +	case 2: +		__raw_writew(cpu_to_le16(value), addr); +		break; +	default: +		__raw_writel(cpu_to_le32(value), addr); +		break; +	} + +	syncio(); +	__raw_writel(0, PCICAR); +	return PCIBIOS_SUCCESSFUL; +} + +static struct pci_ops mcf_pci_ops = { +	.read	= mcf_pci_readconfig, +	.write	= mcf_pci_writeconfig, +}; + +/* + *	IO address space access functions. Pretty strait forward, these are + *	directly mapped in to the IO mapping window. And that is mapped into + *	virtual address space. + */ +u8 mcf_pci_inb(u32 addr) +{ +	return __raw_readb(iospace + (addr & PCI_IO_MASK)); +} +EXPORT_SYMBOL(mcf_pci_inb); + +u16 mcf_pci_inw(u32 addr) +{ +	return le16_to_cpu(__raw_readw(iospace + (addr & PCI_IO_MASK))); +} +EXPORT_SYMBOL(mcf_pci_inw); + +u32 mcf_pci_inl(u32 addr) +{ +	return le32_to_cpu(__raw_readl(iospace + (addr & PCI_IO_MASK))); +} +EXPORT_SYMBOL(mcf_pci_inl); + +void mcf_pci_insb(u32 addr, u8 *buf, u32 len) +{ +	for (; len; len--) +		*buf++ = mcf_pci_inb(addr); +} +EXPORT_SYMBOL(mcf_pci_insb); + +void mcf_pci_insw(u32 addr, u16 *buf, u32 len) +{ +	for (; len; len--) +		*buf++ = mcf_pci_inw(addr); +} +EXPORT_SYMBOL(mcf_pci_insw); + +void mcf_pci_insl(u32 addr, u32 *buf, u32 len) +{ +	for (; len; len--) +		*buf++ = mcf_pci_inl(addr); +} +EXPORT_SYMBOL(mcf_pci_insl); + +void mcf_pci_outb(u8 v, u32 addr) +{ +	__raw_writeb(v, iospace + (addr & PCI_IO_MASK)); +} +EXPORT_SYMBOL(mcf_pci_outb); + +void mcf_pci_outw(u16 v, u32 addr) +{ +	__raw_writew(cpu_to_le16(v), iospace + (addr & PCI_IO_MASK)); +} +EXPORT_SYMBOL(mcf_pci_outw); + +void mcf_pci_outl(u32 v, u32 addr) +{ +	__raw_writel(cpu_to_le32(v), iospace + (addr & PCI_IO_MASK)); +} +EXPORT_SYMBOL(mcf_pci_outl); + +void mcf_pci_outsb(u32 addr, const u8 *buf, u32 len) +{ +	for (; len; len--) +		mcf_pci_outb(*buf++, addr); +} +EXPORT_SYMBOL(mcf_pci_outsb); + +void mcf_pci_outsw(u32 addr, const u16 *buf, u32 len) +{ +	for (; len; len--) +		mcf_pci_outw(*buf++, addr); +} +EXPORT_SYMBOL(mcf_pci_outsw); + +void mcf_pci_outsl(u32 addr, const u32 *buf, u32 len) +{ +	for (; len; len--) +		mcf_pci_outl(*buf++, addr); +} +EXPORT_SYMBOL(mcf_pci_outsl); + +/* + * Initialize the PCI bus registers, and scan the bus. + */ +static struct resource mcf_pci_mem = { +	.name	= "PCI Memory space", +	.start	= PCI_MEM_PA, +	.end	= PCI_MEM_PA + PCI_MEM_SIZE - 1, +	.flags	= IORESOURCE_MEM, +}; + +static struct resource mcf_pci_io = { +	.name	= "PCI IO space", +	.start	= 0x400, +	.end	= 0x10000 - 1, +	.flags	= IORESOURCE_IO, +}; + +/* + * Interrupt mapping and setting. + */ +static int mcf_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) +{ +	int sid; + +	sid = mcf_host_slot2sid[slot]; +	if (sid) +		return mcf_host_irq[sid]; +	return 0; +} + +static int __init mcf_pci_init(void) +{ +	pr_info("ColdFire: PCI bus initialization...\n"); + +	/* Reset the external PCI bus */ +	__raw_writel(PCIGSCR_RESET, PCIGSCR); +	__raw_writel(0, PCITCR); + +	request_resource(&iomem_resource, &mcf_pci_mem); +	request_resource(&iomem_resource, &mcf_pci_io); + +	/* Configure PCI arbiter */ +	__raw_writel(PACR_INTMPRI | PACR_INTMINTE | PACR_EXTMPRI(0x1f) | +		PACR_EXTMINTE(0x1f), PACR); + +	/* Set required multi-function pins for PCI bus use */ +	__raw_writew(0x3ff, MCF_PAR_PCIBG); +	__raw_writew(0x3ff, MCF_PAR_PCIBR); + +	/* Set up config space for local host bus controller */ +	__raw_writel(PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | +		PCI_COMMAND_INVALIDATE, PCISCR); +	__raw_writel(PCICR1_LT(32) | PCICR1_CL(8), PCICR1); +	__raw_writel(0, PCICR2); + +	/* +	 * Set up the initiator windows for memory and IO mapping. +	 * These give the CPU bus access onto the PCI bus. One for each of +	 * PCI memory and IO address spaces. +	 */ +	__raw_writel(WXBTAR(PCI_MEM_PA, PCI_MEM_BA, PCI_MEM_SIZE), +		PCIIW0BTAR); +	__raw_writel(WXBTAR(PCI_IO_PA, PCI_IO_BA, PCI_IO_SIZE), +		PCIIW1BTAR); +	__raw_writel(PCIIWCR_W0_MEM /*| PCIIWCR_W0_MRDL*/ | PCIIWCR_W0_E | +		PCIIWCR_W1_IO | PCIIWCR_W1_E, PCIIWCR); + +	/* +	 * Set up the target windows for access from the PCI bus back to the +	 * CPU bus. All we need is access to system RAM (for mastering). +	 */ +	__raw_writel(CONFIG_RAMBASE, PCIBAR1); +	__raw_writel(CONFIG_RAMBASE | PCITBATR1_E, PCITBATR1); + +	/* Keep a virtual mapping to IO/config space active */ +	iospace = (unsigned long) ioremap(PCI_IO_PA, PCI_IO_SIZE); +	if (iospace == 0) +		return -ENODEV; +	pr_info("Coldfire: PCI IO/config window mapped to 0x%x\n", +		(u32) iospace); + +	/* Turn of PCI reset, and wait for devices to settle */ +	__raw_writel(0, PCIGSCR); +	set_current_state(TASK_UNINTERRUPTIBLE); +	schedule_timeout(msecs_to_jiffies(200)); + +	rootbus = pci_scan_bus(0, &mcf_pci_ops, NULL); +	rootbus->resource[0] = &mcf_pci_io; +	rootbus->resource[1] = &mcf_pci_mem; + +	pci_fixup_irqs(pci_common_swizzle, mcf_pci_map_irq); +	pci_bus_size_bridges(rootbus); +	pci_bus_assign_resources(rootbus); +	pci_enable_bridges(rootbus); +	pci_bus_add_devices(rootbus); +	return 0; +} + +subsys_initcall(mcf_pci_init);  |