[PATCH v4 2/8] irqchip: Add Realtek RTD1295 mux driver

From: Andreas FÃrber
Date: Mon Nov 18 2019 - 21:19:31 EST


This irq mux driver implements the RTD1295 SoC's non-linear mapping
between status and enable bits.

Based in part on QNAP's arch/arm/mach-rtk119x/rtk_irq_mux.c and
Synology's drivers/irqchip/irq-rtk.c code.

Signed-off-by: Andreas FÃrber <afaerber@xxxxxxx>
Cc: Aleix Roca Nonell <kernelrocks@xxxxxxxxx>
Signed-off-by: James Tai <james.tai@xxxxxxxxxxx>
Signed-off-by: Andreas FÃrber <afaerber@xxxxxxx>
---
v3 -> v4:
* Drop no-op .irq_set_affinity callback (Thomas)
* Clear all interrupts (James)
* Updated SPDX-License-identifier
* Use tabular formatting (Thomas)
* Adopt different braces style (Thomas)
* Use raw_spinlock_t (Thomas)
* Shortened callback from isr_to_scpu_int_en_mask to isr_to_int_en_mask (Thomas)
* Fixed of_iomap() error handling to not use IS_ERR()
* Don't mask unmapped NMIs by checking for a non-zero mask
* Cache SCPU_INT_EN to avoid superfluous reads (Thomas)
* Renamed functions and variables from rtd119x to rtd1195

v2 -> v3:
* Adopted spin_lock_irq{save,restore}() (Marc)
* Adopted single-write masking (Marc)
* Adopted misc compatible string
* Introduced explicit bit mapping
* Adopted looped processing of pending interrupts (Marc)
* Replaced unmask implementation with UMSK_ISR write
* Introduced enable/disable ops and dropped no longer needed UART0 quirk

v1 -> v2:
* Renamed struct fields to avoid ambiguity (Marc)
* Refactored offset lookup to avoid per-compatible init functions
* Inserted white lines to clarify balanced locking (Marc)
* Dropped forwarding of set_affinity to GIC (Marc)
* Added spinlocks for consistency (Marc)
* Limited initialization quirk to iso mux
* Fixed spinlock initialization (Andrew)

drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-rtd1195-mux.c | 283 ++++++++++++++++++++++++++++++++++++++
2 files changed, 284 insertions(+)
create mode 100644 drivers/irqchip/irq-rtd1195-mux.c

diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index e806dda690ea..d678881eebc8 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -104,3 +104,4 @@ obj-$(CONFIG_MADERA_IRQ) += irq-madera.o
obj-$(CONFIG_LS1X_IRQ) += irq-ls1x.o
obj-$(CONFIG_TI_SCI_INTR_IRQCHIP) += irq-ti-sci-intr.o
obj-$(CONFIG_TI_SCI_INTA_IRQCHIP) += irq-ti-sci-inta.o
+obj-$(CONFIG_ARCH_REALTEK) += irq-rtd1195-mux.o
diff --git a/drivers/irqchip/irq-rtd1195-mux.c b/drivers/irqchip/irq-rtd1195-mux.c
new file mode 100644
index 000000000000..e6b08438b23c
--- /dev/null
+++ b/drivers/irqchip/irq-rtd1195-mux.c
@@ -0,0 +1,283 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Realtek RTD1295 IRQ mux
+ *
+ * Copyright (c) 2017-2019 Andreas FÃrber
+ */
+
+#include <linux/io.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/slab.h>
+
+struct rtd1195_irq_mux_info {
+ unsigned int isr_offset;
+ unsigned int umsk_isr_offset;
+ unsigned int scpu_int_en_offset;
+ const u32 *isr_to_int_en_mask;
+};
+
+struct rtd1195_irq_mux_data {
+ void __iomem *reg_isr;
+ void __iomem *reg_umsk_isr;
+ void __iomem *reg_scpu_int_en;
+ const struct rtd1195_irq_mux_info *info;
+ int irq;
+ u32 scpu_int_en;
+ struct irq_domain *domain;
+ raw_spinlock_t lock;
+};
+
+static void rtd1195_mux_irq_handle(struct irq_desc *desc)
+{
+ struct rtd1195_irq_mux_data *data = irq_desc_get_handler_data(desc);
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ u32 isr, mask;
+ int i;
+
+ chained_irq_enter(chip, desc);
+
+ isr = readl_relaxed(data->reg_isr);
+
+ while (isr) {
+ i = __ffs(isr);
+ isr &= ~BIT(i);
+
+ mask = data->info->isr_to_int_en_mask[i];
+ if (mask && !(data->scpu_int_en & mask))
+ continue;
+
+ if (!generic_handle_irq(irq_find_mapping(data->domain, i)))
+ writel_relaxed(BIT(i), data->reg_isr);
+ }
+
+ chained_irq_exit(chip, desc);
+}
+
+static void rtd1195_mux_mask_irq(struct irq_data *data)
+{
+ struct rtd1195_irq_mux_data *mux_data = irq_data_get_irq_chip_data(data);
+
+ writel_relaxed(BIT(data->hwirq), mux_data->reg_isr);
+}
+
+static void rtd1195_mux_unmask_irq(struct irq_data *data)
+{
+ struct rtd1195_irq_mux_data *mux_data = irq_data_get_irq_chip_data(data);
+
+ writel_relaxed(BIT(data->hwirq), mux_data->reg_umsk_isr);
+}
+
+static void rtd1195_mux_enable_irq(struct irq_data *data)
+{
+ struct rtd1195_irq_mux_data *mux_data = irq_data_get_irq_chip_data(data);
+ unsigned long flags;
+ u32 mask;
+
+ mask = mux_data->info->isr_to_int_en_mask[data->hwirq];
+ if (!mask)
+ return;
+
+ raw_spin_lock_irqsave(&mux_data->lock, flags);
+
+ mux_data->scpu_int_en |= mask;
+ writel_relaxed(mux_data->scpu_int_en, mux_data->reg_scpu_int_en);
+
+ raw_spin_unlock_irqrestore(&mux_data->lock, flags);
+}
+
+static void rtd1195_mux_disable_irq(struct irq_data *data)
+{
+ struct rtd1195_irq_mux_data *mux_data = irq_data_get_irq_chip_data(data);
+ unsigned long flags;
+ u32 mask;
+
+ mask = mux_data->info->isr_to_int_en_mask[data->hwirq];
+ if (!mask)
+ return;
+
+ raw_spin_lock_irqsave(&mux_data->lock, flags);
+
+ mux_data->scpu_int_en &= ~mask;
+ writel_relaxed(mux_data->scpu_int_en, mux_data->reg_scpu_int_en);
+
+ raw_spin_unlock_irqrestore(&mux_data->lock, flags);
+}
+
+static struct irq_chip rtd1195_mux_irq_chip = {
+ .name = "rtd1195-mux",
+ .irq_mask = rtd1195_mux_mask_irq,
+ .irq_unmask = rtd1195_mux_unmask_irq,
+ .irq_enable = rtd1195_mux_enable_irq,
+ .irq_disable = rtd1195_mux_disable_irq,
+};
+
+static int rtd1195_mux_irq_domain_map(struct irq_domain *d,
+ unsigned int irq, irq_hw_number_t hw)
+{
+ struct rtd1195_irq_mux_data *data = d->host_data;
+
+ irq_set_chip_and_handler(irq, &rtd1195_mux_irq_chip, handle_level_irq);
+ irq_set_chip_data(irq, data);
+ irq_set_probe(irq);
+
+ return 0;
+}
+
+static const struct irq_domain_ops rtd1195_mux_irq_domain_ops = {
+ .xlate = irq_domain_xlate_onecell,
+ .map = rtd1195_mux_irq_domain_map,
+};
+
+enum rtd1295_iso_isr_bits {
+ RTD1295_ISO_ISR_UR0_SHIFT = 2,
+ RTD1295_ISO_ISR_IRDA_SHIFT = 5,
+ RTD1295_ISO_ISR_I2C0_SHIFT = 8,
+ RTD1295_ISO_ISR_I2C1_SHIFT = 11,
+ RTD1295_ISO_ISR_RTC_HSEC_SHIFT = 12,
+ RTD1295_ISO_ISR_RTC_ALARM_SHIFT = 13,
+ RTD1295_ISO_ISR_GPIOA_SHIFT = 19,
+ RTD1295_ISO_ISR_GPIODA_SHIFT = 20,
+ RTD1295_ISO_ISR_GPHY_DV_SHIFT = 29,
+ RTD1295_ISO_ISR_GPHY_AV_SHIFT = 30,
+ RTD1295_ISO_ISR_I2C1_REQ_SHIFT = 31,
+};
+
+static const u32 rtd1295_iso_isr_to_scpu_int_en_mask[32] = {
+ [RTD1295_ISO_ISR_UR0_SHIFT] = BIT(2),
+ [RTD1295_ISO_ISR_IRDA_SHIFT] = BIT(5),
+ [RTD1295_ISO_ISR_I2C0_SHIFT] = BIT(8),
+ [RTD1295_ISO_ISR_I2C1_SHIFT] = BIT(11),
+ [RTD1295_ISO_ISR_RTC_HSEC_SHIFT] = BIT(12),
+ [RTD1295_ISO_ISR_RTC_ALARM_SHIFT] = BIT(13),
+ [RTD1295_ISO_ISR_GPIOA_SHIFT] = BIT(19),
+ [RTD1295_ISO_ISR_GPIODA_SHIFT] = BIT(20),
+ [RTD1295_ISO_ISR_GPHY_DV_SHIFT] = BIT(29),
+ [RTD1295_ISO_ISR_GPHY_AV_SHIFT] = BIT(30),
+ [RTD1295_ISO_ISR_I2C1_REQ_SHIFT] = BIT(31),
+};
+
+enum rtd1295_misc_isr_bits {
+ RTD1295_ISR_UR1_SHIFT = 3,
+ RTD1295_ISR_UR1_TO_SHIFT = 5,
+ RTD1295_ISR_UR2_SHIFT = 8,
+ RTD1295_ISR_RTC_MIN_SHIFT = 10,
+ RTD1295_ISR_RTC_HOUR_SHIFT = 11,
+ RTD1295_ISR_RTC_DATA_SHIFT = 12,
+ RTD1295_ISR_UR2_TO_SHIFT = 13,
+ RTD1295_ISR_I2C5_SHIFT = 14,
+ RTD1295_ISR_I2C4_SHIFT = 15,
+ RTD1295_ISR_GPIOA_SHIFT = 19,
+ RTD1295_ISR_GPIODA_SHIFT = 20,
+ RTD1295_ISR_LSADC0_SHIFT = 21,
+ RTD1295_ISR_LSADC1_SHIFT = 22,
+ RTD1295_ISR_I2C3_SHIFT = 23,
+ RTD1295_ISR_SC0_SHIFT = 24,
+ RTD1295_ISR_I2C2_SHIFT = 26,
+ RTD1295_ISR_GSPI_SHIFT = 27,
+ RTD1295_ISR_FAN_SHIFT = 29,
+};
+
+static const u32 rtd1295_misc_isr_to_scpu_int_en_mask[32] = {
+ [RTD1295_ISR_UR1_SHIFT] = BIT(3),
+ [RTD1295_ISR_UR1_TO_SHIFT] = BIT(5),
+ [RTD1295_ISR_UR2_TO_SHIFT] = BIT(6),
+ [RTD1295_ISR_UR2_SHIFT] = BIT(7),
+ [RTD1295_ISR_RTC_MIN_SHIFT] = BIT(10),
+ [RTD1295_ISR_RTC_HOUR_SHIFT] = BIT(11),
+ [RTD1295_ISR_RTC_DATA_SHIFT] = BIT(12),
+ [RTD1295_ISR_I2C5_SHIFT] = BIT(14),
+ [RTD1295_ISR_I2C4_SHIFT] = BIT(15),
+ [RTD1295_ISR_GPIOA_SHIFT] = BIT(19),
+ [RTD1295_ISR_GPIODA_SHIFT] = BIT(20),
+ [RTD1295_ISR_LSADC0_SHIFT] = BIT(21),
+ [RTD1295_ISR_LSADC1_SHIFT] = BIT(22),
+ [RTD1295_ISR_SC0_SHIFT] = BIT(24),
+ [RTD1295_ISR_I2C2_SHIFT] = BIT(26),
+ [RTD1295_ISR_GSPI_SHIFT] = BIT(27),
+ [RTD1295_ISR_I2C3_SHIFT] = BIT(28),
+ [RTD1295_ISR_FAN_SHIFT] = BIT(29),
+};
+
+static const struct rtd1195_irq_mux_info rtd1295_iso_irq_mux_info = {
+ .isr_offset = 0x0,
+ .umsk_isr_offset = 0x4,
+ .scpu_int_en_offset = 0x40,
+ .isr_to_int_en_mask = rtd1295_iso_isr_to_scpu_int_en_mask,
+};
+
+static const struct rtd1195_irq_mux_info rtd1295_misc_irq_mux_info = {
+ .umsk_isr_offset = 0x8,
+ .isr_offset = 0xc,
+ .scpu_int_en_offset = 0x80,
+ .isr_to_int_en_mask = rtd1295_misc_isr_to_scpu_int_en_mask,
+};
+
+static const struct of_device_id rtd1295_irq_mux_dt_matches[] = {
+ {
+ .compatible = "realtek,rtd1295-iso-irq-mux",
+ .data = &rtd1295_iso_irq_mux_info,
+ },
+ {
+ .compatible = "realtek,rtd1295-misc-irq-mux",
+ .data = &rtd1295_misc_irq_mux_info,
+ },
+ {
+ }
+};
+
+static int __init rtd1195_irq_mux_init(struct device_node *node,
+ struct device_node *parent)
+{
+ struct rtd1195_irq_mux_data *data;
+ const struct of_device_id *match;
+ const struct rtd1195_irq_mux_info *info;
+ void __iomem *base;
+
+ match = of_match_node(rtd1295_irq_mux_dt_matches, node);
+ if (!match)
+ return -EINVAL;
+
+ info = match->data;
+ if (!info)
+ return -EINVAL;
+
+ base = of_iomap(node, 0);
+ if (!base)
+ return -EIO;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->info = info;
+ data->reg_isr = base + info->isr_offset;
+ data->reg_umsk_isr = base + info->umsk_isr_offset;
+ data->reg_scpu_int_en = base + info->scpu_int_en_offset;
+
+ data->irq = irq_of_parse_and_map(node, 0);
+ if (data->irq <= 0) {
+ kfree(data);
+ return -EINVAL;
+ }
+
+ raw_spin_lock_init(&data->lock);
+
+ writel_relaxed(data->scpu_int_en, data->reg_scpu_int_en);
+
+ data->domain = irq_domain_add_linear(node, 32,
+ &rtd1195_mux_irq_domain_ops, data);
+ if (!data->domain) {
+ kfree(data);
+ return -ENOMEM;
+ }
+
+ irq_set_chained_handler_and_data(data->irq, rtd1195_mux_irq_handle, data);
+
+ return 0;
+}
+IRQCHIP_DECLARE(rtd1295_iso_mux, "realtek,rtd1295-iso-irq-mux", rtd1195_irq_mux_init);
+IRQCHIP_DECLARE(rtd1295_misc_mux, "realtek,rtd1295-misc-irq-mux", rtd1195_irq_mux_init);
--
2.16.4