arch/mips/pci/pci-lantiq.c

   1 /*
   2  *  This program is free software; you can redistribute it and/or modify it
   3  *  under the terms of the GNU General Public License version 2 as published
   4  *  by the Free Software Foundation.
   5  *
   6  *  Copyright (C) 2010 John Crispin <blogic@openwrt.org>
   7  */
   8
   9 #include <linux/types.h>
  10 #include <linux/pci.h>
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/delay.h>
  14 #include <linux/mm.h>
  15 #include <linux/vmalloc.h>
  16 #include <linux/module.h>
  17 #include <linux/clk.h>
  18 #include <linux/of_platform.h>
  19 #include <linux/of_gpio.h>
  20 #include <linux/of_irq.h>
  21 #include <linux/of_pci.h>
  22
  23 #include <asm/pci.h>
  24 #include <asm/gpio.h>
  25 #include <asm/addrspace.h>
  26
  27 #include <lantiq_soc.h>
  28 #include <lantiq_irq.h>
  29
  30 #include "pci-lantiq.h"
  31
  32 #define PCI_CR_FCI_ADDR_MAP0            0x00C0
  33 #define PCI_CR_FCI_ADDR_MAP1            0x00C4
  34 #define PCI_CR_FCI_ADDR_MAP2            0x00C8
  35 #define PCI_CR_FCI_ADDR_MAP3            0x00CC
  36 #define PCI_CR_FCI_ADDR_MAP4            0x00D0
  37 #define PCI_CR_FCI_ADDR_MAP5            0x00D4
  38 #define PCI_CR_FCI_ADDR_MAP6            0x00D8
  39 #define PCI_CR_FCI_ADDR_MAP7            0x00DC
  40 #define PCI_CR_CLK_CTRL                 0x0000
  41 #define PCI_CR_PCI_MOD                  0x0030
  42 #define PCI_CR_PC_ARB                   0x0080
  43 #define PCI_CR_FCI_ADDR_MAP11hg         0x00E4
  44 #define PCI_CR_BAR11MASK                0x0044
  45 #define PCI_CR_BAR12MASK                0x0048
  46 #define PCI_CR_BAR13MASK                0x004C
  47 #define PCI_CS_BASE_ADDR1               0x0010
  48 #define PCI_CR_PCI_ADDR_MAP11           0x0064
  49 #define PCI_CR_FCI_BURST_LENGTH         0x00E8
  50 #define PCI_CR_PCI_EOI                  0x002C
  51 #define PCI_CS_STS_CMD                  0x0004
  52
  53 #define PCI_MASTER0_REQ_MASK_2BITS      8
  54 #define PCI_MASTER1_REQ_MASK_2BITS      10
  55 #define PCI_MASTER2_REQ_MASK_2BITS      12
  56 #define INTERNAL_ARB_ENABLE_BIT         0
  57
  58 #define LTQ_CGU_IFCCR           0x0018
  59 #define LTQ_CGU_PCICR           0x0034
  60
  61 #define ltq_pci_w32(x, y)       ltq_w32((x), ltq_pci_membase + (y))
  62 #define ltq_pci_r32(x)          ltq_r32(ltq_pci_membase + (x))
  63
  64 #define ltq_pci_cfg_w32(x, y)   ltq_w32((x), ltq_pci_mapped_cfg + (y))
  65 #define ltq_pci_cfg_r32(x)      ltq_r32(ltq_pci_mapped_cfg + (x))
  66
  67 __iomem void *ltq_pci_mapped_cfg;
  68 static __iomem void *ltq_pci_membase;
  69
  70 static int reset_gpio;
  71 static struct clk *clk_pci, *clk_external;
  72 static struct resource pci_io_resource;
  73 static struct resource pci_mem_resource;
  74 static struct pci_ops pci_ops = {
  75         .read   = ltq_pci_read_config_dword,
  76         .write  = ltq_pci_write_config_dword
  77 };
  78
  79 static struct pci_controller pci_controller = {
  80         .pci_ops        = &pci_ops,
  81         .mem_resource   = &pci_mem_resource,
  82         .mem_offset     = 0x00000000UL,
  83         .io_resource    = &pci_io_resource,
  84         .io_offset      = 0x00000000UL,
  85 };
  86
  87 static inline u32 ltq_calc_bar11mask(void)
  88 {
  89         u32 mem, bar11mask;
  90
  91         /* BAR11MASK value depends on available memory on system. */
  92         mem = get_num_physpages() * PAGE_SIZE;
  93         bar11mask = (0x0ffffff0 & ~((1 << (fls(mem) - 1)) - 1)) | 8;
  94
  95         return bar11mask;
  96 }
  97
  98 static int ltq_pci_startup(struct platform_device *pdev)
  99 {
 100         struct device_node *node = pdev->dev.of_node;
 101         const __be32 *req_mask, *bus_clk;
 102         u32 temp_buffer;
 103
 104         /* get our clocks */
 105         clk_pci = clk_get(&pdev->dev, NULL);
 106         if (IS_ERR(clk_pci)) {
 107                 dev_err(&pdev->dev, "failed to get pci clock\n");
 108                 return PTR_ERR(clk_pci);
 109         }
 110
 111         clk_external = clk_get(&pdev->dev, "external");
 112         if (IS_ERR(clk_external)) {
 113                 clk_put(clk_pci);
 114                 dev_err(&pdev->dev, "failed to get external pci clock\n");
 115                 return PTR_ERR(clk_external);
 116         }
 117
 118         /* read the bus speed that we want */
 119         bus_clk = of_get_property(node, "lantiq,bus-clock", NULL);
 120         if (bus_clk)
 121                 clk_set_rate(clk_pci, *bus_clk);
 122
 123         /* and enable the clocks */
 124         clk_enable(clk_pci);
 125         if (of_find_property(node, "lantiq,external-clock", NULL))
 126                 clk_enable(clk_external);
 127         else
 128                 clk_disable(clk_external);
 129
 130         /* setup reset gpio used by pci */
 131         reset_gpio = of_get_named_gpio(node, "gpio-reset", 0);
 132         if (gpio_is_valid(reset_gpio)) {
 133                 int ret = devm_gpio_request(&pdev->dev,
 134                                                 reset_gpio, "pci-reset");
 135                 if (ret) {
 136                         dev_err(&pdev->dev,
 137                                 "failed to request gpio %d\n", reset_gpio);
 138                         return ret;
 139                 }
 140                 gpio_direction_output(reset_gpio, 1);
 141         }
 142
 143         /* enable auto-switching between PCI and EBU */
 144         ltq_pci_w32(0xa, PCI_CR_CLK_CTRL);
 145
 146         /* busy, i.e. configuration is not done, PCI access has to be retried */
 147         ltq_pci_w32(ltq_pci_r32(PCI_CR_PCI_MOD) & ~(1 << 24), PCI_CR_PCI_MOD);
 148         wmb();
 149         /* BUS Master/IO/MEM access */
 150         ltq_pci_cfg_w32(ltq_pci_cfg_r32(PCI_CS_STS_CMD) | 7, PCI_CS_STS_CMD);
 151
 152         /* enable external 2 PCI masters */
 153         temp_buffer = ltq_pci_r32(PCI_CR_PC_ARB);
 154         /* setup the request mask */
 155         req_mask = of_get_property(node, "req-mask", NULL);
 156         if (req_mask)
 157                 temp_buffer &= ~((*req_mask & 0xf) << 16);
 158         else
 159                 temp_buffer &= ~0xf0000;
 160         /* enable internal arbiter */
 161         temp_buffer |= (1 << INTERNAL_ARB_ENABLE_BIT);
 162         /* enable internal PCI master reqest */
 163         temp_buffer &= (~(3 << PCI_MASTER0_REQ_MASK_2BITS));
 164
 165         /* enable EBU request */
 166         temp_buffer &= (~(3 << PCI_MASTER1_REQ_MASK_2BITS));
 167
 168         /* enable all external masters request */
 169         temp_buffer &= (~(3 << PCI_MASTER2_REQ_MASK_2BITS));
 170         ltq_pci_w32(temp_buffer, PCI_CR_PC_ARB);
 171         wmb();
 172
 173         /* setup BAR memory regions */
 174         ltq_pci_w32(0x18000000, PCI_CR_FCI_ADDR_MAP0);
 175         ltq_pci_w32(0x18400000, PCI_CR_FCI_ADDR_MAP1);
 176         ltq_pci_w32(0x18800000, PCI_CR_FCI_ADDR_MAP2);
 177         ltq_pci_w32(0x18c00000, PCI_CR_FCI_ADDR_MAP3);
 178         ltq_pci_w32(0x19000000, PCI_CR_FCI_ADDR_MAP4);
 179         ltq_pci_w32(0x19400000, PCI_CR_FCI_ADDR_MAP5);
 180         ltq_pci_w32(0x19800000, PCI_CR_FCI_ADDR_MAP6);
 181         ltq_pci_w32(0x19c00000, PCI_CR_FCI_ADDR_MAP7);
 182         ltq_pci_w32(0x1ae00000, PCI_CR_FCI_ADDR_MAP11hg);
 183         ltq_pci_w32(ltq_calc_bar11mask(), PCI_CR_BAR11MASK);
 184         ltq_pci_w32(0, PCI_CR_PCI_ADDR_MAP11);
 185         ltq_pci_w32(0, PCI_CS_BASE_ADDR1);
 186         /* both TX and RX endian swap are enabled */
 187         ltq_pci_w32(ltq_pci_r32(PCI_CR_PCI_EOI) | 3, PCI_CR_PCI_EOI);
 188         wmb();
 189         ltq_pci_w32(ltq_pci_r32(PCI_CR_BAR12MASK) | 0x80000000,
 190                 PCI_CR_BAR12MASK);
 191         ltq_pci_w32(ltq_pci_r32(PCI_CR_BAR13MASK) | 0x80000000,
 192                 PCI_CR_BAR13MASK);
 193         /*use 8 dw burst length */
 194         ltq_pci_w32(0x303, PCI_CR_FCI_BURST_LENGTH);
 195         ltq_pci_w32(ltq_pci_r32(PCI_CR_PCI_MOD) | (1 << 24), PCI_CR_PCI_MOD);
 196         wmb();
 197
 198         /* setup irq line */
 199         ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_PCC_CON) | 0xc, LTQ_EBU_PCC_CON);
 200         ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_PCC_IEN) | 0x10, LTQ_EBU_PCC_IEN);
 201
 202         /* toggle reset pin */
 203         if (gpio_is_valid(reset_gpio)) {
 204                 __gpio_set_value(reset_gpio, 0);
 205                 wmb();
 206                 mdelay(1);
 207                 __gpio_set_value(reset_gpio, 1);
 208         }
 209         return 0;
 210 }
 211
 212 static int ltq_pci_probe(struct platform_device *pdev)
 213 {
 214         struct resource *res_cfg, *res_bridge;
 215
 216         pci_clear_flags(PCI_PROBE_ONLY);
 217
 218         res_cfg = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 219         res_bridge = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 220         if (!res_cfg || !res_bridge) {
 221                 dev_err(&pdev->dev, "missing memory reources\n");
 222                 return -EINVAL;
 223         }
 224
 225         ltq_pci_membase = devm_ioremap_resource(&pdev->dev, res_bridge);
 226         if (IS_ERR(ltq_pci_membase))
 227                 return PTR_ERR(ltq_pci_membase);
 228
 229         ltq_pci_mapped_cfg = devm_ioremap_resource(&pdev->dev, res_cfg);
 230         if (IS_ERR(ltq_pci_mapped_cfg))
 231                 return PTR_ERR(ltq_pci_mapped_cfg);
 232
 233         ltq_pci_startup(pdev);
 234
 235         pci_load_of_ranges(&pci_controller, pdev->dev.of_node);
 236         register_pci_controller(&pci_controller);
 237         return 0;
 238 }
 239
 240 static const struct of_device_id ltq_pci_match[] = {
 241         { .compatible = "lantiq,pci-xway" },
 242         {},
 243 };
 244 MODULE_DEVICE_TABLE(of, ltq_pci_match);
 245
 246 static struct platform_driver ltq_pci_driver = {
 247         .probe = ltq_pci_probe,
 248         .driver = {
 249                 .name = "pci-xway",
 250                 .owner = THIS_MODULE,
 251                 .of_match_table = ltq_pci_match,
 252         },
 253 };
 254
 255 int __init pcibios_init(void)
 256 {
 257         int ret = platform_driver_register(&ltq_pci_driver);
 258         if (ret)
 259                 pr_info("pci-xway: Error registering platform driver!");
 260         return ret;
 261 }
 262
 263 arch_initcall(pcibios_init);