target/linux/brcm2708/patches-4.14/950-0108-bcm2835-aux-Add-aux-interrupt-controller.patch

   1 From 61f87edd9a522d70d979f679d11849d1dc20cedb Mon Sep 17 00:00:00 2001
   2 From: Phil Elwell <phil@raspberrypi.org>
   3 Date: Thu, 23 Mar 2017 16:34:46 +0000
   4 Subject: [PATCH 108/454] bcm2835-aux: Add aux interrupt controller
   5
   6 The AUX block has a shared interrupt line with a register indicating
   7 which devices have active IRQs. Expose this as a nested interrupt
   8 controller to avoid sharing problems.
   9
  10 See: https://github.com/raspberrypi/linux/issues/1484
  11      https://github.com/raspberrypi/linux/issues/1573
  12
  13 Signed-off-by: Phil Elwell <phil@raspberrypi.org>
  14 ---
  15  drivers/clk/bcm/clk-bcm2835-aux.c | 120 ++++++++++++++++++++++++++++++
  16  1 file changed, 120 insertions(+)
  17
  18 --- a/drivers/clk/bcm/clk-bcm2835-aux.c
  19 +++ b/drivers/clk/bcm/clk-bcm2835-aux.c
  20 @@ -17,17 +17,107 @@
  21  #include <linux/clk/bcm2835.h>
  22  #include <linux/module.h>
  23  #include <linux/platform_device.h>
  24 +#include <linux/interrupt.h>
  25 +#include <linux/irqdomain.h>
  26 +#include <linux/of_irq.h>
  27  #include <dt-bindings/clock/bcm2835-aux.h>
  28
  29  #define BCM2835_AUXIRQ         0x00
  30  #define BCM2835_AUXENB         0x04
  31
  32 +#define BCM2835_AUXIRQ_NUM_IRQS  3
  33 +
  34 +#define BCM2835_AUXIRQ_UART_IRQ  0
  35 +#define BCM2835_AUXIRQ_SPI1_IRQ  1
  36 +#define BCM2835_AUXIRQ_SPI2_IRQ  2
  37 +
  38 +#define BCM2835_AUXIRQ_UART_MASK 0x01
  39 +#define BCM2835_AUXIRQ_SPI1_MASK 0x02
  40 +#define BCM2835_AUXIRQ_SPI2_MASK 0x04
  41 +
  42 +#define BCM2835_AUXIRQ_ALL_MASK \
  43 +       (BCM2835_AUXIRQ_UART_MASK | \
  44 +        BCM2835_AUXIRQ_SPI1_MASK | \
  45 +        BCM2835_AUXIRQ_SPI2_MASK)
  46 +
  47 +struct auxirq_state {
  48 +       void __iomem      *status;
  49 +       u32                enables;
  50 +       struct irq_domain *domain;
  51 +       struct regmap     *local_regmap;
  52 +};
  53 +
  54 +static struct auxirq_state auxirq __read_mostly;
  55 +
  56 +static irqreturn_t bcm2835_auxirq_handler(int irq, void *dev_id)
  57 +{
  58 +       u32 stat = readl_relaxed(auxirq.status);
  59 +       u32 masked = stat & auxirq.enables;
  60 +
  61 +       if (masked & BCM2835_AUXIRQ_UART_MASK)
  62 +               generic_handle_irq(irq_linear_revmap(auxirq.domain,
  63 +                                                    BCM2835_AUXIRQ_UART_IRQ));
  64 +
  65 +       if (masked & BCM2835_AUXIRQ_SPI1_MASK)
  66 +               generic_handle_irq(irq_linear_revmap(auxirq.domain,
  67 +                                                    BCM2835_AUXIRQ_SPI1_IRQ));
  68 +
  69 +       if (masked & BCM2835_AUXIRQ_SPI2_MASK)
  70 +               generic_handle_irq(irq_linear_revmap(auxirq.domain,
  71 +                                                    BCM2835_AUXIRQ_SPI2_IRQ));
  72 +
  73 +       return (masked & BCM2835_AUXIRQ_ALL_MASK) ? IRQ_HANDLED : IRQ_NONE;
  74 +}
  75 +
  76 +static int bcm2835_auxirq_xlate(struct irq_domain *d,
  77 +                                struct device_node *ctrlr,
  78 +                                const u32 *intspec, unsigned int intsize,
  79 +                                unsigned long *out_hwirq,
  80 +                                unsigned int *out_type)
  81 +{
  82 +       if (WARN_ON(intsize != 1))
  83 +               return -EINVAL;
  84 +
  85 +       if (WARN_ON(intspec[0] >= BCM2835_AUXIRQ_NUM_IRQS))
  86 +               return -EINVAL;
  87 +
  88 +       *out_hwirq = intspec[0];
  89 +       *out_type = IRQ_TYPE_NONE;
  90 +       return 0;
  91 +}
  92 +
  93 +static void bcm2835_auxirq_mask(struct irq_data *data)
  94 +{
  95 +       irq_hw_number_t hwirq = irqd_to_hwirq(data);
  96 +
  97 +       auxirq.enables &= ~(1 << hwirq);
  98 +}
  99 +
 100 +static void bcm2835_auxirq_unmask(struct irq_data *data)
 101 +{
 102 +       irq_hw_number_t hwirq = irqd_to_hwirq(data);
 103 +
 104 +       auxirq.enables |= (1 << hwirq);
 105 +}
 106 +
 107 +static struct irq_chip bcm2835_auxirq_chip = {
 108 +       .name = "bcm2835-auxirq",
 109 +       .irq_mask = bcm2835_auxirq_mask,
 110 +       .irq_unmask = bcm2835_auxirq_unmask,
 111 +};
 112 +
 113 +static const struct irq_domain_ops bcm2835_auxirq_ops = {
 114 +       .xlate = bcm2835_auxirq_xlate//irq_domain_xlate_onecell
 115 +};
 116 +
 117  static int bcm2835_aux_clk_probe(struct platform_device *pdev)
 118  {
 119         struct device *dev = &pdev->dev;
 120 +       struct device_node *node = dev->of_node;
 121         struct clk_hw_onecell_data *onecell;
 122         const char *parent;
 123         struct clk *parent_clk;
 124 +       int parent_irq;
 125         struct resource *res;
 126         void __iomem *reg, *gate;
 127
 128 @@ -41,6 +131,36 @@ static int bcm2835_aux_clk_probe(struct
 129         if (IS_ERR(reg))
 130                 return PTR_ERR(reg);
 131
 132 +       parent_irq = irq_of_parse_and_map(node, 0);
 133 +       if (parent_irq) {
 134 +               int ret;
 135 +               int i;
 136 +
 137 +               /* Manage the AUX irq as well */
 138 +               auxirq.status = reg + BCM2835_AUXIRQ;
 139 +               auxirq.domain = irq_domain_add_linear(node,
 140 +                                                     BCM2835_AUXIRQ_NUM_IRQS,
 141 +                                                     &bcm2835_auxirq_ops,
 142 +                                                     NULL);
 143 +               if (!auxirq.domain)
 144 +                       return -ENXIO;
 145 +
 146 +               for (i = 0; i < BCM2835_AUXIRQ_NUM_IRQS; i++) {
 147 +                       unsigned int irq = irq_create_mapping(auxirq.domain, i);
 148 +
 149 +                       if (irq == 0)
 150 +                               return -ENXIO;
 151 +
 152 +                       irq_set_chip_and_handler(irq, &bcm2835_auxirq_chip,
 153 +                                                handle_level_irq);
 154 +               }
 155 +
 156 +               ret = devm_request_irq(dev, parent_irq, bcm2835_auxirq_handler,
 157 +                                      0, "bcm2835-auxirq", NULL);
 158 +               if (ret)
 159 +                       return ret;
 160 +       }
 161 +
 162         onecell = devm_kmalloc(dev, sizeof(*onecell) + sizeof(*onecell->hws) *
 163                                BCM2835_AUX_CLOCK_COUNT, GFP_KERNEL);
 164         if (!onecell)