arch/arm/plat-s3c64xx/include/plat/pm-core.h

   1 /* linux/arch/arm/plat-s3c64xx/include/plat/pm-core.h
   2  *
   3  * Copyright 2008 Openmoko, Inc.
   4  * Copyright 2008 Simtec Electronics
   5  *      Ben Dooks <ben@simtec.co.uk>
   6  *      http://armlinux.simtec.co.uk/
   7  *
   8  * S3C64XX - PM core support for arch/arm/plat-s3c/pm.c
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <plat/regs-gpio.h>
  16
  17 static inline void s3c_pm_debug_init_uart(void)
  18 {
  19         u32 tmp = __raw_readl(S3C_PCLK_GATE);
  20
  21         /* As a note, since the S3C64XX UARTs generally have multiple
  22          * clock sources, we simply enable PCLK at the moment and hope
  23          * that the resume settings for the UART are suitable for the
  24          * use with PCLK.
  25          */
  26
  27         tmp |= S3C_CLKCON_PCLK_UART0;
  28         tmp |= S3C_CLKCON_PCLK_UART1;
  29         tmp |= S3C_CLKCON_PCLK_UART2;
  30         tmp |= S3C_CLKCON_PCLK_UART3;
  31
  32         __raw_writel(tmp, S3C_PCLK_GATE);
  33         udelay(10);
  34 }
  35
  36 static inline void s3c_pm_arch_prepare_irqs(void)
  37 {
  38         /* VIC should have already been taken care of */
  39
  40         /* clear any pending EINT0 interrupts */
  41         __raw_writel(__raw_readl(S3C64XX_EINT0PEND), S3C64XX_EINT0PEND);
  42 }
  43
  44 static inline void s3c_pm_arch_stop_clocks(void)
  45 {
  46 }
  47
  48 static inline void s3c_pm_arch_show_resume_irqs(void)
  49 {
  50 }
  51
  52 /* make these defines, we currently do not have any need to change
  53  * the IRQ wake controls depending on the CPU we are running on */
  54
  55 #define s3c_irqwake_eintallow   ((1 << 28) - 1)
  56 #define s3c_irqwake_intallow    (0)
  57
  58 static inline void s3c_pm_arch_update_uart(void __iomem *regs,
  59                                            struct pm_uart_save *save)
  60 {
  61         u32 ucon = __raw_readl(regs + S3C2410_UCON);
  62         u32 ucon_clk = ucon & S3C6400_UCON_CLKMASK;
  63         u32 save_clk = save->ucon & S3C6400_UCON_CLKMASK;
  64         u32 new_ucon;
  65         u32 delta;
  66
  67         /* S3C64XX UART blocks only support level interrupts, so ensure that
  68          * when we restore unused UART blocks we force the level interrupt
  69          * settigs. */
  70         save->ucon |= S3C2410_UCON_TXILEVEL | S3C2410_UCON_RXILEVEL;
  71
  72         /* We have a constraint on changing the clock type of the UART
  73          * between UCLKx and PCLK, so ensure that when we restore UCON
  74          * that the CLK field is correctly modified if the bootloader
  75          * has changed anything.
  76          */
  77         if (ucon_clk != save_clk) {
  78                 new_ucon = save->ucon;
  79                 delta = ucon_clk ^ save_clk;
  80
  81                 /* change from UCLKx => wrong PCLK,
  82                  * either UCLK can be tested for by a bit-test
  83                  * with UCLK0 */
  84                 if (ucon_clk & S3C6400_UCON_UCLK0 &&
  85                     !(save_clk & S3C6400_UCON_UCLK0) &&
  86                     delta & S3C6400_UCON_PCLK2) {
  87                         new_ucon &= ~S3C6400_UCON_UCLK0;
  88                 } else if (delta == S3C6400_UCON_PCLK2) {
  89                         /* as an precaution, don't change from
  90                          * PCLK2 => PCLK or vice-versa */
  91                         new_ucon ^= S3C6400_UCON_PCLK2;
  92                 }
  93
  94                 S3C_PMDBG("ucon change %04x => %04x (save=%04x)\n",
  95                           ucon, new_ucon, save->ucon);
  96                 save->ucon = new_ucon;
  97         }
  98 }