target/linux/brcm2708/patches-4.9/0008-irqchip-irq-bcm2835-Add-2836-FIQ-support.patch

   1 From 78b53021ae0715792fb6a89bd9e7c02fc254be5c Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= <noralf@tronnes.org>
   3 Date: Fri, 23 Oct 2015 16:26:55 +0200
   4 Subject: [PATCH] irqchip: irq-bcm2835: Add 2836 FIQ support
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
  10 ---
  11  drivers/irqchip/irq-bcm2835.c | 43 +++++++++++++++++++++++++++++++++++++++++--
  12  1 file changed, 41 insertions(+), 2 deletions(-)
  13
  14 --- a/drivers/irqchip/irq-bcm2835.c
  15 +++ b/drivers/irqchip/irq-bcm2835.c
  16 @@ -50,8 +50,11 @@
  17  #include <linux/of_irq.h>
  18  #include <linux/irqchip.h>
  19  #include <linux/irqdomain.h>
  20 +#include <linux/mfd/syscon.h>
  21 +#include <linux/regmap.h>
  22
  23  #include <asm/exception.h>
  24 +#include <asm/mach/irq.h>
  25
  26  /* Put the bank and irq (32 bits) into the hwirq */
  27  #define MAKE_HWIRQ(b, n)       (((b) << 5) | (n))
  28 @@ -69,6 +72,9 @@
  29  #define BANK0_VALID_MASK       (BANK0_HWIRQ_MASK | BANK1_HWIRQ | BANK2_HWIRQ \
  30                                         | SHORTCUT1_MASK | SHORTCUT2_MASK)
  31
  32 +#undef ARM_LOCAL_GPU_INT_ROUTING
  33 +#define ARM_LOCAL_GPU_INT_ROUTING 0x0c
  34 +
  35  #define REG_FIQ_CONTROL                0x0c
  36  #define REG_FIQ_ENABLE         0x80
  37  #define REG_FIQ_DISABLE                0
  38 @@ -94,6 +100,7 @@ struct armctrl_ic {
  39         void __iomem *enable[NR_BANKS];
  40         void __iomem *disable[NR_BANKS];
  41         struct irq_domain *domain;
  42 +       struct regmap *local_regmap;
  43  };
  44
  45  static struct armctrl_ic intc __read_mostly;
  46 @@ -127,12 +134,35 @@ static void armctrl_mask_irq(struct irq_
  47
  48  static void armctrl_unmask_irq(struct irq_data *d)
  49  {
  50 -       if (d->hwirq >= NUMBER_IRQS)
  51 +       if (d->hwirq >= NUMBER_IRQS) {
  52 +               if (num_online_cpus() > 1) {
  53 +                       unsigned int data;
  54 +                       int ret;
  55 +
  56 +                       if (!intc.local_regmap) {
  57 +                               pr_err("FIQ is disabled due to missing regmap\n");
  58 +                               return;
  59 +                       }
  60 +
  61 +                       ret = regmap_read(intc.local_regmap,
  62 +                                         ARM_LOCAL_GPU_INT_ROUTING, &data);
  63 +                       if (ret) {
  64 +                               pr_err("Failed to read int routing %d\n", ret);
  65 +                               return;
  66 +                       }
  67 +
  68 +                       data &= ~0xc;
  69 +                       data |= (1 << 2);
  70 +                       regmap_write(intc.local_regmap,
  71 +                                    ARM_LOCAL_GPU_INT_ROUTING, data);
  72 +               }
  73 +
  74                 writel_relaxed(REG_FIQ_ENABLE | hwirq_to_fiq(d->hwirq),
  75                                intc.base + REG_FIQ_CONTROL);
  76 -       else
  77 +       } else {
  78                 writel_relaxed(HWIRQ_BIT(d->hwirq),
  79                                intc.enable[HWIRQ_BANK(d->hwirq)]);
  80 +       }
  81  }
  82
  83  static struct irq_chip armctrl_chip = {
  84 @@ -210,6 +240,15 @@ static int __init armctrl_of_init(struct
  85                 set_handle_irq(bcm2835_handle_irq);
  86         }
  87
  88 +       if (is_2836) {
  89 +               intc.local_regmap =
  90 +                       syscon_regmap_lookup_by_compatible("brcm,bcm2836-arm-local");
  91 +               if (IS_ERR(intc.local_regmap)) {
  92 +                       pr_err("Failed to get local register map. FIQ is disabled for cpus > 1\n");
  93 +                       intc.local_regmap = NULL;
  94 +               }
  95 +       }
  96 +
  97         /* Make a duplicate irq range which is used to enable FIQ */
  98         for (b = 0; b < NR_BANKS; b++) {
  99                 for (i = 0; i < bank_irqs[b]; i++) {