arch/arm/mach-ep93xx/include/mach/uncompress.h

   1 /*
   2  * arch/arm/mach-ep93xx/include/mach/uncompress.h
   3  *
   4  * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
   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 (at
   9  * your option) any later version.
  10  */
  11
  12 #include <mach/ep93xx-regs.h>
  13 #include <asm/mach-types.h>
  14
  15 static unsigned char __raw_readb(unsigned int ptr)
  16 {
  17         return *((volatile unsigned char *)ptr);
  18 }
  19
  20 static unsigned int __raw_readl(unsigned int ptr)
  21 {
  22         return *((volatile unsigned int *)ptr);
  23 }
  24
  25 static void __raw_writeb(unsigned char value, unsigned int ptr)
  26 {
  27         *((volatile unsigned char *)ptr) = value;
  28 }
  29
  30 static void __raw_writel(unsigned int value, unsigned int ptr)
  31 {
  32         *((volatile unsigned int *)ptr) = value;
  33 }
  34
  35 #define PHYS_UART_DATA          (CONFIG_DEBUG_UART_PHYS + 0x00)
  36 #define PHYS_UART_FLAG          (CONFIG_DEBUG_UART_PHYS + 0x18)
  37 #define UART_FLAG_TXFF          0x20
  38
  39 static inline void putc(int c)
  40 {
  41         int i;
  42
  43         for (i = 0; i < 10000; i++) {
  44                 /* Transmit fifo not full? */
  45                 if (!(__raw_readb(PHYS_UART_FLAG) & UART_FLAG_TXFF))
  46                         break;
  47         }
  48
  49         __raw_writeb(c, PHYS_UART_DATA);
  50 }
  51
  52 static inline void flush(void)
  53 {
  54 }
  55
  56
  57 /*
  58  * Some bootloaders don't turn off DMA from the ethernet MAC before
  59  * jumping to linux, which means that we might end up with bits of RX
  60  * status and packet data scribbled over the uncompressed kernel image.
  61  * Work around this by resetting the ethernet MAC before we uncompress.
  62  */
  63 #define PHYS_ETH_SELF_CTL               0x80010020
  64 #define ETH_SELF_CTL_RESET              0x00000001
  65
  66 static void ethernet_reset(void)
  67 {
  68         unsigned int v;
  69
  70         /* Reset the ethernet MAC.  */
  71         v = __raw_readl(PHYS_ETH_SELF_CTL);
  72         __raw_writel(v | ETH_SELF_CTL_RESET, PHYS_ETH_SELF_CTL);
  73
  74         /* Wait for reset to finish.  */
  75         while (__raw_readl(PHYS_ETH_SELF_CTL) & ETH_SELF_CTL_RESET)
  76                 ;
  77 }
  78
  79 #define TS72XX_WDT_CONTROL_PHYS_BASE    0x23800000
  80 #define TS72XX_WDT_FEED_PHYS_BASE       0x23c00000
  81 #define TS72XX_WDT_FEED_VAL             0x05
  82
  83 static void __maybe_unused ts72xx_watchdog_disable(void)
  84 {
  85         __raw_writeb(TS72XX_WDT_FEED_VAL, TS72XX_WDT_FEED_PHYS_BASE);
  86         __raw_writeb(0, TS72XX_WDT_CONTROL_PHYS_BASE);
  87 }
  88
  89 static void arch_decomp_setup(void)
  90 {
  91         if (machine_is_ts72xx())
  92                 ts72xx_watchdog_disable();
  93         ethernet_reset();
  94 }