arch/m68k/coldfire/m54xx.c

   1 /***************************************************************************/
   2
   3 /*
   4  *      m54xx.c  -- platform support for ColdFire 54xx based boards
   5  *
   6  *      Copyright (C) 2010, Philippe De Muyter <phdm@macqel.be>
   7  */
   8
   9 /***************************************************************************/
  10
  11 #include <linux/kernel.h>
  12 #include <linux/param.h>
  13 #include <linux/init.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/io.h>
  16 #include <linux/mm.h>
  17 #include <linux/clk.h>
  18 #include <linux/bootmem.h>
  19 #include <asm/pgalloc.h>
  20 #include <asm/machdep.h>
  21 #include <asm/coldfire.h>
  22 #include <asm/m54xxsim.h>
  23 #include <asm/mcfuart.h>
  24 #include <asm/mcfclk.h>
  25 #include <asm/m54xxgpt.h>
  26 #ifdef CONFIG_MMU
  27 #include <asm/mmu_context.h>
  28 #include <linux/pfn.h>
  29 #endif
  30
  31 /***************************************************************************/
  32
  33 DEFINE_CLK(pll, "pll.0", MCF_CLK);
  34 DEFINE_CLK(sys, "sys.0", MCF_BUSCLK);
  35 DEFINE_CLK(mcfslt0, "mcfslt.0", MCF_BUSCLK);
  36 DEFINE_CLK(mcfslt1, "mcfslt.1", MCF_BUSCLK);
  37 DEFINE_CLK(mcfuart0, "mcfuart.0", MCF_BUSCLK);
  38 DEFINE_CLK(mcfuart1, "mcfuart.1", MCF_BUSCLK);
  39 DEFINE_CLK(mcfuart2, "mcfuart.2", MCF_BUSCLK);
  40 DEFINE_CLK(mcfuart3, "mcfuart.3", MCF_BUSCLK);
  41
  42 struct clk *mcf_clks[] = {
  43         &clk_pll,
  44         &clk_sys,
  45         &clk_mcfslt0,
  46         &clk_mcfslt1,
  47         &clk_mcfuart0,
  48         &clk_mcfuart1,
  49         &clk_mcfuart2,
  50         &clk_mcfuart3,
  51         NULL
  52 };
  53
  54 /***************************************************************************/
  55
  56 static void __init m54xx_uarts_init(void)
  57 {
  58         /* enable io pins */
  59         __raw_writeb(MCF_PAR_PSC_TXD | MCF_PAR_PSC_RXD, MCFGPIO_PAR_PSC0);
  60         __raw_writeb(MCF_PAR_PSC_TXD | MCF_PAR_PSC_RXD | MCF_PAR_PSC_RTS_RTS,
  61                 MCFGPIO_PAR_PSC1);
  62         __raw_writeb(MCF_PAR_PSC_TXD | MCF_PAR_PSC_RXD | MCF_PAR_PSC_RTS_RTS |
  63                 MCF_PAR_PSC_CTS_CTS, MCFGPIO_PAR_PSC2);
  64         __raw_writeb(MCF_PAR_PSC_TXD | MCF_PAR_PSC_RXD, MCFGPIO_PAR_PSC3);
  65 }
  66
  67 /***************************************************************************/
  68
  69 static void mcf54xx_reset(void)
  70 {
  71         /* disable interrupts and enable the watchdog */
  72         asm("movew #0x2700, %sr\n");
  73         __raw_writel(0, MCF_GPT_GMS0);
  74         __raw_writel(MCF_GPT_GCIR_CNT(1), MCF_GPT_GCIR0);
  75         __raw_writel(MCF_GPT_GMS_WDEN | MCF_GPT_GMS_CE | MCF_GPT_GMS_TMS(4),
  76                 MCF_GPT_GMS0);
  77 }
  78
  79 /***************************************************************************/
  80
  81 #ifdef CONFIG_MMU
  82
  83 unsigned long num_pages;
  84
  85 static void __init mcf54xx_bootmem_alloc(void)
  86 {
  87         unsigned long start_pfn;
  88         unsigned long memstart;
  89
  90         /* _rambase and _ramend will be naturally page aligned */
  91         m68k_memory[0].addr = _rambase;
  92         m68k_memory[0].size = _ramend - _rambase;
  93
  94         /* compute total pages in system */
  95         num_pages = PFN_DOWN(_ramend - _rambase);
  96
  97         /* page numbers */
  98         memstart = PAGE_ALIGN(_ramstart);
  99         min_low_pfn = PFN_DOWN(_rambase);
 100         start_pfn = PFN_DOWN(memstart);
 101         max_pfn = max_low_pfn = PFN_DOWN(_ramend);
 102         high_memory = (void *)_ramend;
 103
 104         m68k_virt_to_node_shift = fls(_ramend - _rambase - 1) - 6;
 105         module_fixup(NULL, __start_fixup, __stop_fixup);
 106
 107         /* setup bootmem data */
 108         m68k_setup_node(0);
 109         memstart += init_bootmem_node(NODE_DATA(0), start_pfn,
 110                 min_low_pfn, max_low_pfn);
 111         free_bootmem_node(NODE_DATA(0), memstart, _ramend - memstart);
 112 }
 113
 114 #endif /* CONFIG_MMU */
 115
 116 /***************************************************************************/
 117
 118 void __init config_BSP(char *commandp, int size)
 119 {
 120 #ifdef CONFIG_MMU
 121         mcf54xx_bootmem_alloc();
 122         mmu_context_init();
 123 #endif
 124         mach_reset = mcf54xx_reset;
 125         mach_sched_init = hw_timer_init;
 126         m54xx_uarts_init();
 127 }
 128
 129 /***************************************************************************/