Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / dma / ipu / ipu_irq.c
diff --git a/kernel/drivers/dma/ipu/ipu_irq.c b/kernel/drivers/dma/ipu/ipu_irq.c
new file mode 100644 (file)
index 0000000..2e284a4
--- /dev/null
@@ -0,0 +1,415 @@
+/*
+ * Copyright (C) 2008
+ * Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/spinlock.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/dma/ipu-dma.h>
+
+#include "ipu_intern.h"
+
+/*
+ * Register read / write - shall be inlined by the compiler
+ */
+static u32 ipu_read_reg(struct ipu *ipu, unsigned long reg)
+{
+       return __raw_readl(ipu->reg_ipu + reg);
+}
+
+static void ipu_write_reg(struct ipu *ipu, u32 value, unsigned long reg)
+{
+       __raw_writel(value, ipu->reg_ipu + reg);
+}
+
+
+/*
+ * IPU IRQ chip driver
+ */
+
+#define IPU_IRQ_NR_FN_BANKS 3
+#define IPU_IRQ_NR_ERR_BANKS 2
+#define IPU_IRQ_NR_BANKS (IPU_IRQ_NR_FN_BANKS + IPU_IRQ_NR_ERR_BANKS)
+
+struct ipu_irq_bank {
+       unsigned int    control;
+       unsigned int    status;
+       struct ipu      *ipu;
+};
+
+static struct ipu_irq_bank irq_bank[IPU_IRQ_NR_BANKS] = {
+       /* 3 groups of functional interrupts */
+       {
+               .control        = IPU_INT_CTRL_1,
+               .status         = IPU_INT_STAT_1,
+       }, {
+               .control        = IPU_INT_CTRL_2,
+               .status         = IPU_INT_STAT_2,
+       }, {
+               .control        = IPU_INT_CTRL_3,
+               .status         = IPU_INT_STAT_3,
+       },
+       /* 2 groups of error interrupts */
+       {
+               .control        = IPU_INT_CTRL_4,
+               .status         = IPU_INT_STAT_4,
+       }, {
+               .control        = IPU_INT_CTRL_5,
+               .status         = IPU_INT_STAT_5,
+       },
+};
+
+struct ipu_irq_map {
+       unsigned int            irq;
+       int                     source;
+       struct ipu_irq_bank     *bank;
+       struct ipu              *ipu;
+};
+
+static struct ipu_irq_map irq_map[CONFIG_MX3_IPU_IRQS];
+/* Protects allocations from the above array of maps */
+static DEFINE_MUTEX(map_lock);
+/* Protects register accesses and individual mappings */
+static DEFINE_RAW_SPINLOCK(bank_lock);
+
+static struct ipu_irq_map *src2map(unsigned int src)
+{
+       int i;
+
+       for (i = 0; i < CONFIG_MX3_IPU_IRQS; i++)
+               if (irq_map[i].source == src)
+                       return irq_map + i;
+
+       return NULL;
+}
+
+static void ipu_irq_unmask(struct irq_data *d)
+{
+       struct ipu_irq_map *map = irq_data_get_irq_chip_data(d);
+       struct ipu_irq_bank *bank;
+       uint32_t reg;
+       unsigned long lock_flags;
+
+       raw_spin_lock_irqsave(&bank_lock, lock_flags);
+
+       bank = map->bank;
+       if (!bank) {
+               raw_spin_unlock_irqrestore(&bank_lock, lock_flags);
+               pr_err("IPU: %s(%u) - unmapped!\n", __func__, d->irq);
+               return;
+       }
+
+       reg = ipu_read_reg(bank->ipu, bank->control);
+       reg |= (1UL << (map->source & 31));
+       ipu_write_reg(bank->ipu, reg, bank->control);
+
+       raw_spin_unlock_irqrestore(&bank_lock, lock_flags);
+}
+
+static void ipu_irq_mask(struct irq_data *d)
+{
+       struct ipu_irq_map *map = irq_data_get_irq_chip_data(d);
+       struct ipu_irq_bank *bank;
+       uint32_t reg;
+       unsigned long lock_flags;
+
+       raw_spin_lock_irqsave(&bank_lock, lock_flags);
+
+       bank = map->bank;
+       if (!bank) {
+               raw_spin_unlock_irqrestore(&bank_lock, lock_flags);
+               pr_err("IPU: %s(%u) - unmapped!\n", __func__, d->irq);
+               return;
+       }
+
+       reg = ipu_read_reg(bank->ipu, bank->control);
+       reg &= ~(1UL << (map->source & 31));
+       ipu_write_reg(bank->ipu, reg, bank->control);
+
+       raw_spin_unlock_irqrestore(&bank_lock, lock_flags);
+}
+
+static void ipu_irq_ack(struct irq_data *d)
+{
+       struct ipu_irq_map *map = irq_data_get_irq_chip_data(d);
+       struct ipu_irq_bank *bank;
+       unsigned long lock_flags;
+
+       raw_spin_lock_irqsave(&bank_lock, lock_flags);
+
+       bank = map->bank;
+       if (!bank) {
+               raw_spin_unlock_irqrestore(&bank_lock, lock_flags);
+               pr_err("IPU: %s(%u) - unmapped!\n", __func__, d->irq);
+               return;
+       }
+
+       ipu_write_reg(bank->ipu, 1UL << (map->source & 31), bank->status);
+       raw_spin_unlock_irqrestore(&bank_lock, lock_flags);
+}
+
+/**
+ * ipu_irq_status() - returns the current interrupt status of the specified IRQ.
+ * @irq:       interrupt line to get status for.
+ * @return:    true if the interrupt is pending/asserted or false if the
+ *             interrupt is not pending.
+ */
+bool ipu_irq_status(unsigned int irq)
+{
+       struct ipu_irq_map *map = irq_get_chip_data(irq);
+       struct ipu_irq_bank *bank;
+       unsigned long lock_flags;
+       bool ret;
+
+       raw_spin_lock_irqsave(&bank_lock, lock_flags);
+       bank = map->bank;
+       ret = bank && ipu_read_reg(bank->ipu, bank->status) &
+               (1UL << (map->source & 31));
+       raw_spin_unlock_irqrestore(&bank_lock, lock_flags);
+
+       return ret;
+}
+
+/**
+ * ipu_irq_map() - map an IPU interrupt source to an IRQ number
+ * @source:    interrupt source bit position (see below)
+ * @return:    mapped IRQ number or negative error code
+ *
+ * The source parameter has to be explained further. On i.MX31 IPU has 137 IRQ
+ * sources, they are broken down in 5 32-bit registers, like 32, 32, 24, 32, 17.
+ * However, the source argument of this function is not the sequence number of
+ * the possible IRQ, but rather its bit position. So, first interrupt in fourth
+ * register has source number 96, and not 88. This makes calculations easier,
+ * and also provides forward compatibility with any future IPU implementations
+ * with any interrupt bit assignments.
+ */
+int ipu_irq_map(unsigned int source)
+{
+       int i, ret = -ENOMEM;
+       struct ipu_irq_map *map;
+
+       might_sleep();
+
+       mutex_lock(&map_lock);
+       map = src2map(source);
+       if (map) {
+               pr_err("IPU: Source %u already mapped to IRQ %u\n", source, map->irq);
+               ret = -EBUSY;
+               goto out;
+       }
+
+       for (i = 0; i < CONFIG_MX3_IPU_IRQS; i++) {
+               if (irq_map[i].source < 0) {
+                       unsigned long lock_flags;
+
+                       raw_spin_lock_irqsave(&bank_lock, lock_flags);
+                       irq_map[i].source = source;
+                       irq_map[i].bank = irq_bank + source / 32;
+                       raw_spin_unlock_irqrestore(&bank_lock, lock_flags);
+
+                       ret = irq_map[i].irq;
+                       pr_debug("IPU: mapped source %u to IRQ %u\n",
+                                source, ret);
+                       break;
+               }
+       }
+out:
+       mutex_unlock(&map_lock);
+
+       if (ret < 0)
+               pr_err("IPU: couldn't map source %u: %d\n", source, ret);
+
+       return ret;
+}
+
+/**
+ * ipu_irq_map() - map an IPU interrupt source to an IRQ number
+ * @source:    interrupt source bit position (see ipu_irq_map())
+ * @return:    0 or negative error code
+ */
+int ipu_irq_unmap(unsigned int source)
+{
+       int i, ret = -EINVAL;
+
+       might_sleep();
+
+       mutex_lock(&map_lock);
+       for (i = 0; i < CONFIG_MX3_IPU_IRQS; i++) {
+               if (irq_map[i].source == source) {
+                       unsigned long lock_flags;
+
+                       pr_debug("IPU: unmapped source %u from IRQ %u\n",
+                                source, irq_map[i].irq);
+
+                       raw_spin_lock_irqsave(&bank_lock, lock_flags);
+                       irq_map[i].source = -EINVAL;
+                       irq_map[i].bank = NULL;
+                       raw_spin_unlock_irqrestore(&bank_lock, lock_flags);
+
+                       ret = 0;
+                       break;
+               }
+       }
+       mutex_unlock(&map_lock);
+
+       return ret;
+}
+
+/* Chained IRQ handler for IPU error interrupt */
+static void ipu_irq_err(unsigned int irq, struct irq_desc *desc)
+{
+       struct ipu *ipu = irq_get_handler_data(irq);
+       u32 status;
+       int i, line;
+
+       for (i = IPU_IRQ_NR_FN_BANKS; i < IPU_IRQ_NR_BANKS; i++) {
+               struct ipu_irq_bank *bank = irq_bank + i;
+
+               raw_spin_lock(&bank_lock);
+               status = ipu_read_reg(ipu, bank->status);
+               /*
+                * Don't think we have to clear all interrupts here, they will
+                * be acked by ->handle_irq() (handle_level_irq). However, we
+                * might want to clear unhandled interrupts after the loop...
+                */
+               status &= ipu_read_reg(ipu, bank->control);
+               raw_spin_unlock(&bank_lock);
+               while ((line = ffs(status))) {
+                       struct ipu_irq_map *map;
+
+                       line--;
+                       status &= ~(1UL << line);
+
+                       raw_spin_lock(&bank_lock);
+                       map = src2map(32 * i + line);
+                       if (map)
+                               irq = map->irq;
+                       raw_spin_unlock(&bank_lock);
+
+                       if (!map) {
+                               pr_err("IPU: Interrupt on unmapped source %u bank %d\n",
+                                      line, i);
+                               continue;
+                       }
+                       generic_handle_irq(irq);
+               }
+       }
+}
+
+/* Chained IRQ handler for IPU function interrupt */
+static void ipu_irq_fn(unsigned int irq, struct irq_desc *desc)
+{
+       struct ipu *ipu = irq_desc_get_handler_data(desc);
+       u32 status;
+       int i, line;
+
+       for (i = 0; i < IPU_IRQ_NR_FN_BANKS; i++) {
+               struct ipu_irq_bank *bank = irq_bank + i;
+
+               raw_spin_lock(&bank_lock);
+               status = ipu_read_reg(ipu, bank->status);
+               /* Not clearing all interrupts, see above */
+               status &= ipu_read_reg(ipu, bank->control);
+               raw_spin_unlock(&bank_lock);
+               while ((line = ffs(status))) {
+                       struct ipu_irq_map *map;
+
+                       line--;
+                       status &= ~(1UL << line);
+
+                       raw_spin_lock(&bank_lock);
+                       map = src2map(32 * i + line);
+                       if (map)
+                               irq = map->irq;
+                       raw_spin_unlock(&bank_lock);
+
+                       if (!map) {
+                               pr_err("IPU: Interrupt on unmapped source %u bank %d\n",
+                                      line, i);
+                               continue;
+                       }
+                       generic_handle_irq(irq);
+               }
+       }
+}
+
+static struct irq_chip ipu_irq_chip = {
+       .name           = "ipu_irq",
+       .irq_ack        = ipu_irq_ack,
+       .irq_mask       = ipu_irq_mask,
+       .irq_unmask     = ipu_irq_unmask,
+};
+
+/* Install the IRQ handler */
+int __init ipu_irq_attach_irq(struct ipu *ipu, struct platform_device *dev)
+{
+       unsigned int irq, i;
+       int irq_base = irq_alloc_descs(-1, 0, CONFIG_MX3_IPU_IRQS,
+                                      numa_node_id());
+
+       if (irq_base < 0)
+               return irq_base;
+
+       for (i = 0; i < IPU_IRQ_NR_BANKS; i++)
+               irq_bank[i].ipu = ipu;
+
+       for (i = 0; i < CONFIG_MX3_IPU_IRQS; i++) {
+               int ret;
+
+               irq = irq_base + i;
+               ret = irq_set_chip(irq, &ipu_irq_chip);
+               if (ret < 0)
+                       return ret;
+               ret = irq_set_chip_data(irq, irq_map + i);
+               if (ret < 0)
+                       return ret;
+               irq_map[i].ipu = ipu;
+               irq_map[i].irq = irq;
+               irq_map[i].source = -EINVAL;
+               irq_set_handler(irq, handle_level_irq);
+#ifdef CONFIG_ARM
+               set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+#endif
+       }
+
+       irq_set_handler_data(ipu->irq_fn, ipu);
+       irq_set_chained_handler(ipu->irq_fn, ipu_irq_fn);
+
+       irq_set_handler_data(ipu->irq_err, ipu);
+       irq_set_chained_handler(ipu->irq_err, ipu_irq_err);
+
+       ipu->irq_base = irq_base;
+
+       return 0;
+}
+
+void ipu_irq_detach_irq(struct ipu *ipu, struct platform_device *dev)
+{
+       unsigned int irq, irq_base;
+
+       irq_base = ipu->irq_base;
+
+       irq_set_chained_handler(ipu->irq_fn, NULL);
+       irq_set_handler_data(ipu->irq_fn, NULL);
+
+       irq_set_chained_handler(ipu->irq_err, NULL);
+       irq_set_handler_data(ipu->irq_err, NULL);
+
+       for (irq = irq_base; irq < irq_base + CONFIG_MX3_IPU_IRQS; irq++) {
+#ifdef CONFIG_ARM
+               set_irq_flags(irq, 0);
+#endif
+               irq_set_chip(irq, NULL);
+               irq_set_chip_data(irq, NULL);
+       }
+}