imask.c 1.9 KB

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  1. // SPDX-License-Identifier: GPL-2.0
  2. /*
  3. * arch/sh/kernel/cpu/irq/imask.c
  4. *
  5. * Copyright (C) 1999, 2000 Niibe Yutaka
  6. *
  7. * Simple interrupt handling using IMASK of SR register.
  8. *
  9. */
  10. /* NOTE: Will not work on level 15 */
  11. #include <linux/ptrace.h>
  12. #include <linux/errno.h>
  13. #include <linux/kernel_stat.h>
  14. #include <linux/signal.h>
  15. #include <linux/sched.h>
  16. #include <linux/interrupt.h>
  17. #include <linux/init.h>
  18. #include <linux/bitops.h>
  19. #include <linux/spinlock.h>
  20. #include <linux/cache.h>
  21. #include <linux/irq.h>
  22. #include <linux/bitmap.h>
  23. #include <asm/irq.h>
  24. /* Bitmap of IRQ masked */
  25. #define IMASK_PRIORITY 15
  26. static DECLARE_BITMAP(imask_mask, IMASK_PRIORITY);
  27. static int interrupt_priority;
  28. static inline void set_interrupt_registers(int ip)
  29. {
  30. unsigned long __dummy;
  31. asm volatile(
  32. #ifdef CONFIG_CPU_HAS_SR_RB
  33. "ldc %2, r6_bank\n\t"
  34. #endif
  35. "stc sr, %0\n\t"
  36. "and #0xf0, %0\n\t"
  37. "shlr2 %0\n\t"
  38. "cmp/eq #0x3c, %0\n\t"
  39. "bt/s 1f ! CLI-ed\n\t"
  40. " stc sr, %0\n\t"
  41. "and %1, %0\n\t"
  42. "or %2, %0\n\t"
  43. "ldc %0, sr\n"
  44. "1:"
  45. : "=&z" (__dummy)
  46. : "r" (~0xf0), "r" (ip << 4)
  47. : "t");
  48. }
  49. static void mask_imask_irq(struct irq_data *data)
  50. {
  51. unsigned int irq = data->irq;
  52. clear_bit(irq, imask_mask);
  53. if (interrupt_priority < IMASK_PRIORITY - irq)
  54. interrupt_priority = IMASK_PRIORITY - irq;
  55. set_interrupt_registers(interrupt_priority);
  56. }
  57. static void unmask_imask_irq(struct irq_data *data)
  58. {
  59. unsigned int irq = data->irq;
  60. set_bit(irq, imask_mask);
  61. interrupt_priority = IMASK_PRIORITY -
  62. find_first_zero_bit(imask_mask, IMASK_PRIORITY);
  63. set_interrupt_registers(interrupt_priority);
  64. }
  65. static struct irq_chip imask_irq_chip = {
  66. .name = "SR.IMASK",
  67. .irq_mask = mask_imask_irq,
  68. .irq_unmask = unmask_imask_irq,
  69. .irq_mask_ack = mask_imask_irq,
  70. };
  71. void make_imask_irq(unsigned int irq)
  72. {
  73. irq_set_chip_and_handler_name(irq, &imask_irq_chip, handle_level_irq,
  74. "level");
  75. }