diff options
| -rw-r--r-- | arch/powerpc/Kconfig | 1 | ||||
| -rw-r--r-- | arch/powerpc/platforms/cell/Makefile | 4 | ||||
| -rw-r--r-- | arch/powerpc/platforms/cell/io-workarounds.c | 346 |
3 files changed, 349 insertions, 2 deletions
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 3e89d9d3493..9547aacc319 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -476,6 +476,7 @@ config PPC_CELL_NATIVE select PPC_CELL select PPC_DCR_MMIO select PPC_OF_PLATFORM_PCI + select PPC_INDIRECT_IO select MPIC default n diff --git a/arch/powerpc/platforms/cell/Makefile b/arch/powerpc/platforms/cell/Makefile index 0f31db7a50a..62c011e8092 100644 --- a/arch/powerpc/platforms/cell/Makefile +++ b/arch/powerpc/platforms/cell/Makefile @@ -1,6 +1,6 @@ obj-$(CONFIG_PPC_CELL_NATIVE) += interrupt.o iommu.o setup.o \ - cbe_regs.o spider-pic.o pervasive.o \ - pmu.o + cbe_regs.o spider-pic.o \ + pervasive.o pmu.o io-workarounds.o obj-$(CONFIG_CBE_RAS) += ras.o obj-$(CONFIG_CBE_THERM) += cbe_thermal.o diff --git a/arch/powerpc/platforms/cell/io-workarounds.c b/arch/powerpc/platforms/cell/io-workarounds.c new file mode 100644 index 00000000000..580d4259591 --- /dev/null +++ b/arch/powerpc/platforms/cell/io-workarounds.c @@ -0,0 +1,346 @@ +/* + * Copyright (C) 2006 Benjamin Herrenschmidt <benh@kernel.crashing.org> + * IBM, Corp. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#undef DEBUG + +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/pci.h> +#include <asm/io.h> +#include <asm/machdep.h> +#include <asm/pci-bridge.h> +#include <asm/ppc-pci.h> + + +#define SPIDER_PCI_REG_BASE 0xd000 +#define SPIDER_PCI_VCI_CNTL_STAT 0x0110 +#define SPIDER_PCI_DUMMY_READ 0x0810 +#define SPIDER_PCI_DUMMY_READ_BASE 0x0814 + +/* Undefine that to re-enable bogus prefetch + * + * Without that workaround, the chip will do bogus prefetch past + * page boundary from system memory. This setting will disable that, + * though the documentation is unclear as to the consequences of doing + * so, either purely performances, or possible misbehaviour... It's not + * clear wether the chip can handle unaligned accesses at all without + * prefetching enabled. + * + * For now, things appear to be behaving properly with that prefetching + * disabled and IDE, possibly because IDE isn't doing any unaligned + * access. + */ +#define SPIDER_DISABLE_PREFETCH + +#define MAX_SPIDERS 2 + +static struct spider_pci_bus { + void __iomem *regs; + unsigned long mmio_start; + unsigned long mmio_end; + unsigned long pio_vstart; + unsigned long pio_vend; +} spider_pci_busses[MAX_SPIDERS]; +static int spider_pci_count; + +static struct spider_pci_bus *spider_pci_find(unsigned long vaddr, + unsigned long paddr) +{ + int i; + + for (i = 0; i < spider_pci_count; i++) { + struct spider_pci_bus *bus = &spider_pci_busses[i]; + if (paddr && paddr >= bus->mmio_start && paddr < bus->mmio_end) + return bus; + if (vaddr && vaddr >= bus->pio_vstart && vaddr < bus->pio_vend) + return bus; + } + return NULL; +} + +static void spider_io_flush(const volatile void __iomem *addr) +{ + struct spider_pci_bus *bus; + int token; + + /* Get platform token (set by ioremap) from address */ + token = PCI_GET_ADDR_TOKEN(addr); + + /* Fast path if we have a non-0 token, it indicates which bus we + * are on. + * + * If the token is 0, that means either the the ioremap was done + * before we initialized this layer, or it's a PIO operation. We + * fallback to a low path in this case. Hopefully, internal devices + * which are ioremap'ed early should use in_XX/out_XX functions + * instead of the PCI ones and thus not suffer from the slowdown. + * + * Also note that currently, the workaround will not work for areas + * that are not mapped with PTEs (bolted in the hash table). This + * is the case for ioremaps done very early at boot (before + * mem_init_done) and includes the mapping of the ISA IO space. + * + * Fortunately, none of the affected devices is expected to do DMA + * and thus there should be no problem in practice. + * + * In order to improve performances, we only do the PTE search for + * addresses falling in the PHB IO space area. That means it will + * not work for hotplug'ed PHBs but those don't exist with Spider. + */ + if (token && token <= spider_pci_count) + bus = &spider_pci_busses[token - 1]; + else { + unsigned long vaddr, paddr; + pte_t *ptep; + + /* Fixup physical address */ + vaddr = (unsigned long)PCI_FIX_ADDR(addr); + + /* Check if it's in allowed range for PIO */ + if (vaddr < PHBS_IO_BASE || vaddr >= IMALLOC_BASE) + return; + + /* Try to find a PTE. If not, clear the paddr, we'll do + * a vaddr only lookup (PIO only) + */ + ptep = find_linux_pte(init_mm.pgd, vaddr); + if (ptep == NULL) + paddr = 0; + else + paddr = pte_pfn(*ptep) << PAGE_SHIFT; + + bus = spider_pci_find(vaddr, paddr); + if (bus == NULL) + return; + } + + /* Now do the workaround + */ + (void)in_be32(bus->regs + SPIDER_PCI_DUMMY_READ); +} + +static u8 spider_readb(const volatile void __iomem *addr) +{ + u8 val = __do_readb(addr); + spider_io_flush(addr); + return val; +} + +static u16 spider_readw(const volatile void __iomem *addr) +{ + u16 val = __do_readw(addr); + spider_io_flush(addr); + return val; +} + +static u32 spider_readl(const volatile void __iomem *addr) +{ + u32 val = __do_readl(addr); + spider_io_flush(addr); + return val; +} + +static u64 spider_readq(const volatile void __iomem *addr) +{ + u64 val = __do_readq(addr); + spider_io_flush(addr); + return val; +} + +static u16 spider_readw_be(const volatile void __iomem *addr) +{ + u16 val = __do_readw_be(addr); + spider_io_flush(addr); + return val; +} + +static u32 spider_readl_be(const volatile void __iomem *addr) +{ + u32 val = __do_readl_be(addr); + spider_io_flush(addr); + return val; +} + +static u64 spider_readq_be(const volatile void __iomem *addr) +{ + u64 val = __do_readq_be(addr); + spider_io_flush(addr); + return val; +} + +static void spider_readsb(const volatile void __iomem *addr, void *buf, + unsigned long count) +{ + __do_readsb(addr, buf, count); + spider_io_flush(addr); +} + +static void spider_readsw(const volatile void __iomem *addr, void *buf, + unsigned long count) +{ + __do_readsw(addr, buf, count); + spider_io_flush(addr); +} + +static void spider_readsl(const volatile void __iomem *addr, void *buf, + unsigned long count) +{ + __do_readsl(addr, buf, count); + spider_io_flush(addr); +} + +static void spider_memcpy_fromio(void *dest, const volatile void __iomem *src, + unsigned long n) +{ + __do_memcpy_fromio(dest, src, n); + spider_io_flush(src); +} + + +static void __iomem * spider_ioremap(unsigned long addr, unsigned long size, + unsigned long flags) +{ + struct spider_pci_bus *bus; + void __iomem *res = __ioremap(addr, size, flags); + int busno; + + pr_debug("spider_ioremap(0x%lx, 0x%lx, 0x%lx) -> 0x%p\n", + addr, size, flags, res); + + bus = spider_pci_find(0, addr); + if (bus != NULL) { + busno = bus - spider_pci_busses; + pr_debug(" found bus %d, setting token\n", busno); + PCI_SET_ADDR_TOKEN(res, busno + 1); + } + pr_debug(" result=0x%p\n", res); + + return res; +} + +static void __init spider_pci_setup_chip(struct spider_pci_bus *bus) +{ +#ifdef SPIDER_DISABLE_PREFETCH + u32 val = in_be32(bus->regs + SPIDER_PCI_VCI_CNTL_STAT); + pr_debug(" PVCI_Control_Status was 0x%08x\n", val); + out_be32(bus->regs + SPIDER_PCI_VCI_CNTL_STAT, val | 0x8); +#endif + + /* Configure the dummy address for the workaround */ + out_be32(bus->regs + SPIDER_PCI_DUMMY_READ_BASE, 0x80000000); +} + +static void __init spider_pci_add_one(struct pci_controller *phb) +{ + struct spider_pci_bus *bus = &spider_pci_busses[spider_pci_count]; + struct device_node *np = phb->arch_data; + struct resource rsrc; + void __iomem *regs; + + if (spider_pci_count >= MAX_SPIDERS) { + printk(KERN_ERR "Too many spider bridges, workarounds" + " disabled for %s\n", np->full_name); + return; + } + + /* Get the registers for the beast */ + if (of_address_to_resource(np, 0, &rsrc)) { + printk(KERN_ERR "Failed to get registers for spider %s" + " workarounds disabled\n", np->full_name); + return; + } + + /* Mask out some useless bits in there to get to the base of the + * spider chip + */ + rsrc.start &= ~0xfffffffful; + + /* Map them */ + regs = ioremap(rsrc.start + SPIDER_PCI_REG_BASE, 0x1000); + if (regs == NULL) { + printk(KERN_ERR "Failed to map registers for spider %s" + " workarounds disabled\n", np->full_name); + return; + } + + spider_pci_count++; + + /* We assume spiders only have one MMIO resource */ + bus->mmio_start = phb->mem_resources[0].start; + bus->mmio_end = phb->mem_resources[0].end + 1; + + bus->pio_vstart = (unsigned long)phb->io_base_virt; + bus->pio_vend = bus->pio_vstart + phb->pci_io_size; + + bus->regs = regs; + + printk(KERN_INFO "PCI: Spider MMIO workaround for %s\n",np->full_name); + + pr_debug(" mmio (P) = 0x%016lx..0x%016lx\n", + bus->mmio_start, bus->mmio_end); + pr_debug(" pio (V) = 0x%016lx..0x%016lx\n", + bus->pio_vstart, bus->pio_vend); + pr_debug(" regs (P) = 0x%016lx (V) = 0x%p\n", + rsrc.start + SPIDER_PCI_REG_BASE, bus->regs); + + spider_pci_setup_chip(bus); +} + +static struct ppc_pci_io __initdata spider_pci_io = { + .readb = spider_readb, + .readw = spider_readw, + .readl = spider_readl, + .readq = spider_readq, + .readw_be = spider_readw_be, + .readl_be = spider_readl_be, + .readq_be = spider_readq_be, + .readsb = spider_readsb, + .readsw = spider_readsw, + .readsl = spider_readsl, + .memcpy_fromio = spider_memcpy_fromio, +}; + +static int __init spider_pci_workaround_init(void) +{ + struct pci_controller *phb; + + if (!machine_is(cell)) + return 0; + + /* Find spider bridges. We assume they have been all probed + * in setup_arch(). If that was to change, we would need to + * update this code to cope with dynamically added busses + */ + list_for_each_entry(phb, &hose_list, list_node) { + struct device_node *np = phb->arch_data; + const char *model = get_property(np, "model", NULL); + + /* If no model property or name isn't exactly "pci", skip */ + if (model == NULL || strcmp(np->name, "pci")) + continue; + /* If model is not "Spider", skip */ + if (strcmp(model, "Spider")) + continue; + spider_pci_add_one(phb); + } + + /* No Spider PCI found, exit */ + if (spider_pci_count == 0) + return 0; + + /* Setup IO callbacks. We only setup MMIO reads. PIO reads will + * fallback to MMIO reads (though without a token, thus slower) + */ + ppc_pci_io = spider_pci_io; + + /* Setup ioremap callback */ + ppc_md.ioremap = spider_ioremap; + + return 0; +} +arch_initcall(spider_pci_workaround_init); |