target/linux/mcs814x/files-3.18/arch/arm/mach-mcs814x/common.c

   1 /*
   2  * arch/arm/mach-mcs814x/common.c
   3  *
   4  * Core functions for Moschip MCS814x SoCs
   5  *
   6  * This file is licensed under the terms of the GNU General Public
   7  * License version 2.  This program is licensed "as is" without any
   8  * warranty of any kind, whether express or implied.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/io.h>
  14 #include <linux/gpio.h>
  15 #include <linux/of.h>
  16 #include <linux/of_address.h>
  17 #include <linux/reboot.h>
  18
  19 #include <asm/setup.h>
  20 #include <asm/mach-types.h>
  21 #include <asm/mach/arch.h>
  22 #include <mach/mcs814x.h>
  23 #include <mach/cpu.h>
  24 #include <asm/pgtable.h>
  25 #include <asm/mach/map.h>
  26
  27 void __iomem *mcs814x_sysdbg_base;
  28
  29 static struct map_desc mcs814x_io_desc[] __initdata = {
  30         {
  31                 .virtual        = MCS814X_IO_BASE,
  32                 .pfn            = __phys_to_pfn(MCS814X_IO_START),
  33                 .length         = MCS814X_IO_SIZE,
  34                 .type           = MT_DEVICE
  35         },
  36 };
  37
  38 struct cpu_mode {
  39         const char *name;
  40         int gpio_start;
  41         int gpio_end;
  42 };
  43
  44 static const struct cpu_mode cpu_modes[] = {
  45         {
  46                 .name           = "I2S",
  47                 .gpio_start     = 4,
  48                 .gpio_end       = 8,
  49         },
  50         {
  51                 .name           = "UART",
  52                 .gpio_start     = 4,
  53                 .gpio_end       = 9,
  54         },
  55         {
  56                 .name           = "External MII",
  57                 .gpio_start     = 0,
  58                 .gpio_end       = 16,
  59         },
  60         {
  61                 .name           = "Normal",
  62                 .gpio_start     = -1,
  63                 .gpio_end       = -1,
  64         },
  65 };
  66
  67 static void mcs814x_eth_hardware_filter_set(u8 value)
  68 {
  69         u32 reg;
  70
  71         reg = readl_relaxed(MCS814X_VIRT_BASE + MCS814X_DBGLED);
  72         if (value)
  73                 reg |= 0x80;
  74         else
  75                 reg &= ~0x80;
  76         writel_relaxed(reg, MCS814X_VIRT_BASE + MCS814X_DBGLED);
  77 }
  78
  79 static void mcs814x_eth_led_cfg_set(u8 cfg)
  80 {
  81         u32 reg;
  82
  83         reg = readl_relaxed(mcs814x_sysdbg_base + SYSDBG_BS2);
  84         reg &= ~LED_CFG_MASK;
  85         reg |= cfg;
  86         writel_relaxed(reg, mcs814x_sysdbg_base + SYSDBG_BS2);
  87 }
  88
  89 static void mcs814x_eth_buffer_shifting_set(u8 value)
  90 {
  91         u8 reg;
  92
  93         reg = readb_relaxed(mcs814x_sysdbg_base + SYSDBG_SYSCTL_MAC);
  94         if (value)
  95                 reg |= BUF_SHIFT_BIT;
  96         else
  97                 reg &= ~BUF_SHIFT_BIT;
  98         writeb_relaxed(reg, mcs814x_sysdbg_base + SYSDBG_SYSCTL_MAC);
  99 }
 100
 101 static struct of_device_id mcs814x_eth_ids[] __initdata = {
 102         { .compatible = "moschip,nuport-mac", },
 103         { /* sentinel */ },
 104 };
 105
 106 /* Configure platform specific knobs based on ethernet device node
 107  * properties */
 108 static void mcs814x_eth_init(void)
 109 {
 110         struct device_node *np;
 111         const unsigned int *intspec;
 112
 113         np = of_find_matching_node(NULL, mcs814x_eth_ids);
 114         if (!np)
 115                 return;
 116
 117         /* hardware filter must always be enabled */
 118         mcs814x_eth_hardware_filter_set(1);
 119
 120         intspec = of_get_property(np, "nuport-mac,buffer-shifting", NULL);
 121         if (!intspec)
 122                 mcs814x_eth_buffer_shifting_set(0);
 123         else
 124                 mcs814x_eth_buffer_shifting_set(1);
 125
 126         intspec = of_get_property(np, "nuport-mac,link-activity", NULL);
 127         if (intspec)
 128                 mcs814x_eth_led_cfg_set(be32_to_cpup(intspec));
 129
 130         of_node_put(np);
 131 }
 132
 133 void __init mcs814x_init_machine(void)
 134 {
 135         u32 bs2, cpu_mode;
 136         int gpio;
 137
 138         bs2 = readl_relaxed(mcs814x_sysdbg_base + SYSDBG_BS2);
 139         cpu_mode = (bs2 >> CPU_MODE_SHIFT) & CPU_MODE_MASK;
 140
 141         pr_info("CPU mode: %s\n", cpu_modes[cpu_mode].name);
 142
 143         /* request the gpios since the pins are muxed for functionnality */
 144         for (gpio = cpu_modes[cpu_mode].gpio_start;
 145                 gpio == cpu_modes[cpu_mode].gpio_end; gpio++) {
 146                 if (gpio != -1)
 147                         gpio_request(gpio, cpu_modes[cpu_mode].name);
 148         }
 149
 150         mcs814x_eth_init();
 151 }
 152
 153 void __init mcs814x_map_io(void)
 154 {
 155         iotable_init(mcs814x_io_desc, ARRAY_SIZE(mcs814x_io_desc));
 156
 157         mcs814x_sysdbg_base = ioremap(MCS814X_IO_START + MCS814X_SYSDBG,
 158                                         MCS814X_SYSDBG_SIZE);
 159         if (!mcs814x_sysdbg_base)
 160                 panic("unable to remap sysdbg base");
 161 }
 162
 163 void mcs814x_restart(enum reboot_mode mode, const char *cmd)
 164 {
 165         writel_relaxed(~(1 << 31), mcs814x_sysdbg_base);
 166 }