timer.c 1.9 KB

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  1. // SPDX-License-Identifier: GPL-2.0+
  2. /*
  3. * Copyright (C) 2011 Vladimir Zapolskiy <vz@mleia.com>
  4. */
  5. #include <common.h>
  6. #include <time.h>
  7. #include <asm/arch/cpu.h>
  8. #include <asm/arch/clk.h>
  9. #include <asm/arch/timer.h>
  10. #include <asm/io.h>
  11. static struct timer_regs *timer0 = (struct timer_regs *)TIMER0_BASE;
  12. static struct timer_regs *timer1 = (struct timer_regs *)TIMER1_BASE;
  13. static struct clk_pm_regs *clk = (struct clk_pm_regs *)CLK_PM_BASE;
  14. static void lpc32xx_timer_clock(u32 bit, int enable)
  15. {
  16. if (enable)
  17. setbits_le32(&clk->timclk_ctrl1, bit);
  18. else
  19. clrbits_le32(&clk->timclk_ctrl1, bit);
  20. }
  21. static void lpc32xx_timer_reset(struct timer_regs *timer, u32 freq)
  22. {
  23. writel(TIMER_TCR_COUNTER_RESET, &timer->tcr);
  24. writel(TIMER_TCR_COUNTER_DISABLE, &timer->tcr);
  25. writel(0, &timer->tc);
  26. writel(0, &timer->pr);
  27. /* Count mode is every rising PCLK edge */
  28. writel(TIMER_CTCR_MODE_TIMER, &timer->ctcr);
  29. /* Set prescale counter value */
  30. writel((get_periph_clk_rate() / freq) - 1, &timer->pr);
  31. /* Ensure that the counter is not reset when matching TC */
  32. writel(0, &timer->mcr);
  33. }
  34. static void lpc32xx_timer_count(struct timer_regs *timer, int enable)
  35. {
  36. if (enable)
  37. writel(TIMER_TCR_COUNTER_ENABLE, &timer->tcr);
  38. else
  39. writel(TIMER_TCR_COUNTER_DISABLE, &timer->tcr);
  40. }
  41. int timer_init(void)
  42. {
  43. lpc32xx_timer_clock(CLK_TIMCLK_TIMER0, 1);
  44. lpc32xx_timer_reset(timer0, CONFIG_SYS_HZ);
  45. lpc32xx_timer_count(timer0, 1);
  46. return 0;
  47. }
  48. ulong get_timer(ulong base)
  49. {
  50. return readl(&timer0->tc) - base;
  51. }
  52. void __udelay(unsigned long usec)
  53. {
  54. lpc32xx_timer_clock(CLK_TIMCLK_TIMER1, 1);
  55. lpc32xx_timer_reset(timer1, CONFIG_SYS_HZ * 1000);
  56. lpc32xx_timer_count(timer1, 1);
  57. while (readl(&timer1->tc) < usec)
  58. /* NOP */;
  59. lpc32xx_timer_count(timer1, 0);
  60. lpc32xx_timer_clock(CLK_TIMCLK_TIMER1, 0);
  61. }
  62. unsigned long long get_ticks(void)
  63. {
  64. return get_timer(0);
  65. }
  66. ulong get_tbclk(void)
  67. {
  68. return CONFIG_SYS_HZ;
  69. }