arch/sh/kernel/cpu/irq/ipr.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Interrupt handling for IPR-based IRQ.
   4  *
   5  * Copyright (C) 1999  Niibe Yutaka & Takeshi Yaegashi
   6  * Copyright (C) 2000  Kazumoto Kojima
   7  * Copyright (C) 2003  Takashi Kusuda <kusuda-takashi@hitachi-ul.co.jp>
   8  * Copyright (C) 2006  Paul Mundt
   9  *
  10  * Supported system:
  11  *      On-chip supporting modules (TMU, RTC, etc.).
  12  *      On-chip supporting modules for SH7709/SH7709A/SH7729.
  13  *      Hitachi SolutionEngine external I/O:
  14  *              MS7709SE01, MS7709ASE01, and MS7750SE01
  15  */
  16 #include <linux/init.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/io.h>
  19 #include <linux/irq.h>
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/topology.h>
  23
  24 static inline struct ipr_desc *get_ipr_desc(struct irq_data *data)
  25 {
  26         struct irq_chip *chip = irq_data_get_irq_chip(data);
  27         return container_of(chip, struct ipr_desc, chip);
  28 }
  29
  30 static void disable_ipr_irq(struct irq_data *data)
  31 {
  32         struct ipr_data *p = irq_data_get_irq_chip_data(data);
  33         unsigned long addr = get_ipr_desc(data)->ipr_offsets[p->ipr_idx];
  34         /* Set the priority in IPR to 0 */
  35         __raw_writew(__raw_readw(addr) & (0xffff ^ (0xf << p->shift)), addr);
  36         (void)__raw_readw(addr);        /* Read back to flush write posting */
  37 }
  38
  39 static void enable_ipr_irq(struct irq_data *data)
  40 {
  41         struct ipr_data *p = irq_data_get_irq_chip_data(data);
  42         unsigned long addr = get_ipr_desc(data)->ipr_offsets[p->ipr_idx];
  43         /* Set priority in IPR back to original value */
  44         __raw_writew(__raw_readw(addr) | (p->priority << p->shift), addr);
  45 }
  46
  47 /*
  48  * The shift value is now the number of bits to shift, not the number of
  49  * bits/4. This is to make it easier to read the value directly from the
  50  * datasheets. The IPR address is calculated using the ipr_offset table.
  51  */
  52 void register_ipr_controller(struct ipr_desc *desc)
  53 {
  54         int i;
  55
  56         desc->chip.irq_mask = disable_ipr_irq;
  57         desc->chip.irq_unmask = enable_ipr_irq;
  58
  59         for (i = 0; i < desc->nr_irqs; i++) {
  60                 struct ipr_data *p = desc->ipr_data + i;
  61                 int res;
  62
  63                 BUG_ON(p->ipr_idx >= desc->nr_offsets);
  64                 BUG_ON(!desc->ipr_offsets[p->ipr_idx]);
  65
  66                 res = irq_alloc_desc_at(p->irq, numa_node_id());
  67                 if (unlikely(res != p->irq && res != -EEXIST)) {
  68                         printk(KERN_INFO "can not get irq_desc for %d\n",
  69                                p->irq);
  70                         continue;
  71                 }
  72
  73                 disable_irq_nosync(p->irq);
  74                 irq_set_chip_and_handler_name(p->irq, &desc->chip,
  75                                               handle_level_irq, "level");
  76                 irq_set_chip_data(p->irq, p);
  77                 disable_ipr_irq(irq_get_irq_data(p->irq));
  78         }
  79 }
  80 EXPORT_SYMBOL(register_ipr_controller);