arch/powerpc/platforms/cell/spider-pci.c

   1 /*
   2  * IO workarounds for PCI on Celleb/Cell platform
   3  *
   4  * (C) Copyright 2006-2007 TOSHIBA CORPORATION
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #undef DEBUG
  22
  23 #include <linux/kernel.h>
  24 #include <linux/of_platform.h>
  25 #include <linux/slab.h>
  26 #include <linux/io.h>
  27
  28 #include <asm/ppc-pci.h>
  29 #include <asm/pci-bridge.h>
  30 #include <asm/io-workarounds.h>
  31
  32 #define SPIDER_PCI_DISABLE_PREFETCH
  33
  34 struct spiderpci_iowa_private {
  35         void __iomem *regs;
  36 };
  37
  38 static void spiderpci_io_flush(struct iowa_bus *bus)
  39 {
  40         struct spiderpci_iowa_private *priv;
  41         u32 val;
  42
  43         priv = bus->private;
  44         val = in_be32(priv->regs + SPIDER_PCI_DUMMY_READ);
  45         iosync();
  46 }
  47
  48 #define SPIDER_PCI_MMIO_READ(name, ret)                                 \
  49 static ret spiderpci_##name(const PCI_IO_ADDR addr)                     \
  50 {                                                                       \
  51         ret val = __do_##name(addr);                                    \
  52         spiderpci_io_flush(iowa_mem_find_bus(addr));                    \
  53         return val;                                                     \
  54 }
  55
  56 #define SPIDER_PCI_MMIO_READ_STR(name)                                  \
  57 static void spiderpci_##name(const PCI_IO_ADDR addr, void *buf,         \
  58                              unsigned long count)                       \
  59 {                                                                       \
  60         __do_##name(addr, buf, count);                                  \
  61         spiderpci_io_flush(iowa_mem_find_bus(addr));                    \
  62 }
  63
  64 SPIDER_PCI_MMIO_READ(readb, u8)
  65 SPIDER_PCI_MMIO_READ(readw, u16)
  66 SPIDER_PCI_MMIO_READ(readl, u32)
  67 SPIDER_PCI_MMIO_READ(readq, u64)
  68 SPIDER_PCI_MMIO_READ(readw_be, u16)
  69 SPIDER_PCI_MMIO_READ(readl_be, u32)
  70 SPIDER_PCI_MMIO_READ(readq_be, u64)
  71 SPIDER_PCI_MMIO_READ_STR(readsb)
  72 SPIDER_PCI_MMIO_READ_STR(readsw)
  73 SPIDER_PCI_MMIO_READ_STR(readsl)
  74
  75 static void spiderpci_memcpy_fromio(void *dest, const PCI_IO_ADDR src,
  76                                     unsigned long n)
  77 {
  78         __do_memcpy_fromio(dest, src, n);
  79         spiderpci_io_flush(iowa_mem_find_bus(src));
  80 }
  81
  82 static int __init spiderpci_pci_setup_chip(struct pci_controller *phb,
  83                                            void __iomem *regs)
  84 {
  85         void *dummy_page_va;
  86         dma_addr_t dummy_page_da;
  87
  88 #ifdef SPIDER_PCI_DISABLE_PREFETCH
  89         u32 val = in_be32(regs + SPIDER_PCI_VCI_CNTL_STAT);
  90         pr_debug("SPIDER_IOWA:PVCI_Control_Status was 0x%08x\n", val);
  91         out_be32(regs + SPIDER_PCI_VCI_CNTL_STAT, val | 0x8);
  92 #endif /* SPIDER_PCI_DISABLE_PREFETCH */
  93
  94         /* setup dummy read */
  95         /*
  96          * On CellBlade, we can't know that which XDR memory is used by
  97          * kmalloc() to allocate dummy_page_va.
  98          * In order to imporve the performance, the XDR which is used to
  99          * allocate dummy_page_va is the nearest the spider-pci.
 100          * We have to select the CBE which is the nearest the spider-pci
 101          * to allocate memory from the best XDR, but I don't know that
 102          * how to do.
 103          *
 104          * Celleb does not have this problem, because it has only one XDR.
 105          */
 106         dummy_page_va = kmalloc(PAGE_SIZE, GFP_KERNEL);
 107         if (!dummy_page_va) {
 108                 pr_err("SPIDERPCI-IOWA:Alloc dummy_page_va failed.\n");
 109                 return -1;
 110         }
 111
 112         dummy_page_da = dma_map_single(phb->parent, dummy_page_va,
 113                                        PAGE_SIZE, DMA_FROM_DEVICE);
 114         if (dma_mapping_error(phb->parent, dummy_page_da)) {
 115                 pr_err("SPIDER-IOWA:Map dummy page filed.\n");
 116                 kfree(dummy_page_va);
 117                 return -1;
 118         }
 119
 120         out_be32(regs + SPIDER_PCI_DUMMY_READ_BASE, dummy_page_da);
 121
 122         return 0;
 123 }
 124
 125 int __init spiderpci_iowa_init(struct iowa_bus *bus, void *data)
 126 {
 127         void __iomem *regs = NULL;
 128         struct spiderpci_iowa_private *priv;
 129         struct device_node *np = bus->phb->dn;
 130         struct resource r;
 131         unsigned long offset = (unsigned long)data;
 132
 133         pr_debug("SPIDERPCI-IOWA:Bus initialize for spider(%s)\n",
 134                  np->full_name);
 135
 136         priv = kzalloc(sizeof(struct spiderpci_iowa_private), GFP_KERNEL);
 137         if (!priv) {
 138                 pr_err("SPIDERPCI-IOWA:"
 139                        "Can't allocate struct spiderpci_iowa_private");
 140                 return -1;
 141         }
 142
 143         if (of_address_to_resource(np, 0, &r)) {
 144                 pr_err("SPIDERPCI-IOWA:Can't get resource.\n");
 145                 goto error;
 146         }
 147
 148         regs = ioremap(r.start + offset, SPIDER_PCI_REG_SIZE);
 149         if (!regs) {
 150                 pr_err("SPIDERPCI-IOWA:ioremap failed.\n");
 151                 goto error;
 152         }
 153         priv->regs = regs;
 154         bus->private = priv;
 155
 156         if (spiderpci_pci_setup_chip(bus->phb, regs))
 157                 goto error;
 158
 159         return 0;
 160
 161 error:
 162         kfree(priv);
 163         bus->private = NULL;
 164
 165         if (regs)
 166                 iounmap(regs);
 167
 168         return -1;
 169 }
 170
 171 struct ppc_pci_io spiderpci_ops = {
 172         .readb = spiderpci_readb,
 173         .readw = spiderpci_readw,
 174         .readl = spiderpci_readl,
 175         .readq = spiderpci_readq,
 176         .readw_be = spiderpci_readw_be,
 177         .readl_be = spiderpci_readl_be,
 178         .readq_be = spiderpci_readq_be,
 179         .readsb = spiderpci_readsb,
 180         .readsw = spiderpci_readsw,
 181         .readsl = spiderpci_readsl,
 182         .memcpy_fromio = spiderpci_memcpy_fromio,
 183 };
 184