[DO NOT MERGE v5 18/37] irqchip: SH7751 IRL external encoder with enable gate.

Yoshinori Sato
2023-12-05T10:13:13Z

SH7751 have 15 level external interrupt.
It is typically connected to the CPU through a priority encoder
that can suppress requests.
This driver provides a way to control those hardware with irqchip.

Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
---
drivers/irqchip/Kconfig | 7 +
drivers/irqchip/Makefile | 2 +
drivers/irqchip/irq-renesas-sh7751irl.c | 227 ++++++++++++++++++++++++
3 files changed, 236 insertions(+)
create mode 100644 drivers/irqchip/irq-renesas-sh7751irl.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 658523f65b1d..2a061c01f381 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -687,4 +687,11 @@ config RENESAS_SH7751_INTC
Support for the Renesas SH7751 On-chip interrupt controller.
And external interrupt encoder for some targets.

+config RENESAS_SH7751IRL_INTC
+ bool "Renesas SH7751 based target IRL encoder support."
+ depends on RENESAS_SH7751_INTC
+ help
+ Support for External Interrupt encoder
+ on the some Renesas SH7751 based target.
+
endmenu
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 26c91d075e25..91df16726b1f 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -121,3 +121,5 @@ obj-$(CONFIG_APPLE_AIC) += irq-apple-aic.o
obj-$(CONFIG_MCHP_EIC) += irq-mchp-eic.o
obj-$(CONFIG_SUNPLUS_SP7021_INTC) += irq-sp7021-intc.o
obj-$(CONFIG_RENESAS_SH7751_INTC) += irq-renesas-sh7751.o
+obj-$(CONFIG_RENESAS_SH7751IRL_INTC) += irq-renesas-sh7751irl.o
+
diff --git a/drivers/irqchip/irq-renesas-sh7751irl.c b/drivers/irqchip/irq-renesas-sh7751irl.c
new file mode 100644
index 000000000000..99ee5bf9fb1e
--- /dev/null
+++ b/drivers/irqchip/irq-renesas-sh7751irl.c
@@ -0,0 +1,227 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SH7751 based board IRL encoder driver
+ * (Renesas RTS7751R2D / IO DATA DEVICE LANDISK, USL-5P)
+ *
+ * Copyright (C) 2023 Yoshinori Sato
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irqdomain.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <linux/bitops.h>
+
+struct sh7751irl_intc_priv {
+ struct irq_domain *irq_domain;
+ void __iomem *base;
+ unsigned int width;
+ bool invert;
+ u32 enable_bit[NR_IRL];
+};
+
+static inline unsigned long get_reg(void __iomem *addr, unsigned int w)
+{
+ switch (w) {
+ case 8:
+ return __raw_readb(addr);
+ case 16:
+ return __raw_readw(addr);
+ case 32:
+ return __raw_readl(addr);
+ default:
+ /* The size is checked when reading the properties. */
+ pr_err("%s: Invalid width %d", __FILE__, w);
+ return 0;
+ }
+}
+
+static inline void set_reg(void __iomem *addr, unsigned int w, unsigned long val)
+{
+ switch (w) {
+ case 8:
+ __raw_writeb(val, addr);
+ break;
+ case 16:
+ __raw_writew(val, addr);
+ break;
+ case 32:
+ __raw_writel(val, addr);
+ break;
+ default:
+ pr_err("%s: Invalid width %d", __FILE__, w);
+ }
+}
+
+static inline struct sh7751irl_intc_priv *irq_data_to_priv(struct irq_data *data)
+{
+ return data->domain->host_data;
+}
+
+static void irl_endisable(struct irq_data *data, unsigned int enable)
+{
+ struct sh7751irl_intc_priv *priv;
+ unsigned long val;
+ unsigned int irl;
+
+ priv = irq_data_to_priv(data);
+ irl = irqd_to_hwirq(data) - IRL_BASE_IRQ;
+
+ if (irl < NR_IRL && priv->enable_bit[irl] < priv->width) {
+ if (priv->invert)
+ enable = !enable;
+
+ val = get_reg(priv->base, priv->width);
+ if (enable)
+ set_bit(priv->enable_bit[irl], &val);
+ else
+ clear_bit(priv->enable_bit[irl], &val);
+ set_reg(priv->base, priv->width, val);
+ } else {
+ pr_err("%s: Invalid register define in IRL %u", __FILE__, irl);
+ }
+}
+
+static void sh7751irl_intc_disable_irq(struct irq_data *data)
+{
+ irl_endisable(data, 0);
+}
+
+static void sh7751irl_intc_enable_irq(struct irq_data *data)
+{
+ irl_endisable(data, 1);
+}
+
+static struct irq_chip sh7751irl_intc_chip = {
+ .name = "SH7751IRL-INTC",
+ .irq_enable = sh7751irl_intc_enable_irq,
+ .irq_disable = sh7751irl_intc_disable_irq,
+};
+
+static int sh7751irl_intc_map(struct irq_domain *h, unsigned int virq,
+ irq_hw_number_t hw_irq_num)
+{
+ irq_set_chip_and_handler(virq, &sh7751irl_intc_chip, handle_level_irq);
+ irq_get_irq_data(virq)->chip_data = h->host_data;
+ irq_modify_status(virq, IRQ_NOREQUEST, IRQ_NOPROBE);
+ return 0;
+}
+
+static int sh7751irl_intc_translate(struct irq_domain *domain,
+ struct irq_fwspec *fwspec, unsigned long *hwirq,
+ unsigned int *type)
+{
+ if (fwspec->param[0] > NR_IRL)
+ return -EINVAL;
+
+ switch (fwspec->param_count) {
+ case 2:
+ *type = fwspec->param[1];
+ fallthrough;
+ case 1:
+ *hwirq = fwspec->param[0] + IRL_BASE_IRQ;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static const struct irq_domain_ops sh7751irl_intc_domain_ops = {
+ .map = sh7751irl_intc_map,
+ .translate = sh7751irl_intc_translate,
+};
+
+static int __init load_irq_bit(struct device_node *node, struct sh7751irl_intc_priv *priv)
+{
+ struct property *enable_map;
+ const __be32 *p;
+ u32 nr_bits;
+ u32 irl;
+ int ret;
+
+ /* Fill in unused */
+ memset(priv->enable_bit, ~0, sizeof(priv->enable_bit));
+
+ enable_map = of_find_property(node, "renesas,enable-bit", &nr_bits);
+ if (IS_ERR(enable_map))
+ return PTR_ERR(enable_map);
+
+ nr_bits /= sizeof(u32);
+ /* 2words per entry. */
+ if (nr_bits % 2)
+ return -EINVAL;
+ nr_bits /= 2;
+ if (nr_bits > NR_IRL)
+ return -EINVAL;
+
+ ret = nr_bits;
+ p = NULL;
+ for (; nr_bits > 0; nr_bits--) {
+ /* 1st word - IRL */
+ p = of_prop_next_u32(enable_map, p, &irl);
+ if (!p || irl > NR_IRL)
+ return -EINVAL;
+ /* 2nd word - enable bit index */
+ p = of_prop_next_u32(enable_map, p, &priv->enable_bit[irl]);
+ if (priv->enable_bit[irl] >= priv->width)
+ return -EINVAL;
+ }
+ return ret;
+}
+
+static int __init sh7751irl_init(struct device_node *node, struct device_node *parent)
+{
+ struct sh7751irl_intc_priv *priv;
+ struct irq_domain *d;
+ void __iomem *base;
+ int ret = 0;
+
+ base = of_iomap(node, 0);
+ if (!base)
+ ret = -EINVAL;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->base = base;
+ of_property_read_u32(node, "renesas,width", &priv->width);
+ if (priv->width != 8 && priv->width != 16 && priv->width != 32) {
+ pr_err("%pOFP: Invalid register width.\n", node);
+ ret = -EINVAL;
+ goto error;
+ }
+
+ priv->invert = of_property_read_bool(node, "renesas,set-to-disable");
+
+ ret = load_irq_bit(node, priv);
+ if (ret < 0) {
+ pr_err("%pOFP: Invalid register define.\n", node);
+ goto error;
+ }
+
+ d = irq_domain_add_tree(node, &sh7751irl_intc_domain_ops, priv);
+ if (d == NULL) {
+ pr_err("%pOFP: cannot initialize irq domain\n", node);
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ priv->irq_domain = d;
+ irq_domain_update_bus_token(d, DOMAIN_BUS_WIRED);
+ pr_info("%pOFP: SH7751 External Interrupt encoder (input=%d)", node, ret);
+ return 0;
+error:
+ kfree(priv);
+ return ret;
+}
+
+IRQCHIP_DECLARE(renesas_sh7751_irl, "renesas,sh7751-irl-ext", sh7751irl_init);
--
2.39.2