[PATCH v4 1/5] gpio: gxp: Add HPE GXP GPIO

From: nick . hawkins
Date: Wed Jun 21 2023 - 17:36:14 EST


From: Nick Hawkins <nick.hawkins@xxxxxxx>

The GXP SoC supports GPIO on multiple interfaces. The interfaces are
CPLD and Host. The GPIOs is a combination of both physical and virtual
I/O across the interfaces. The gpio-gxp driver specifically covers the
CSM(physical), FN2(virtual), and VUHC(virtual) which are the host. The
driver supports interrupts from the host.

Signed-off-by: Nick Hawkins <nick.hawkins@xxxxxxx>

---

v4:
*Moved gpio-gxp-pl.c to a separate commit.
*Moved regmap_config out of function and made it static const
*Removed unnecessary variables
*Removed redundant conditional
*Modified regmap_read switch statements to calculate offset and mask
then read at end.
*Removed use of -EOPNOTSUPP
*Removed redundant casting
*Switched generic_handle_irq -> generic_handle_domain_irq
*Used GENMASK where applicable
*Used bitmap_xor and for_each_bit_set
*Made GPIO chip const and marked as a template (in the name)
*Made irq_chip const and immutable
*Removed casting in one case
*Corrected check on devm_gpiochip_add_data
*Remove dev_err_probe on platform_get_irq
*Changed return 0 to devm_request_irq
v3:
*Remove shared variables with gxp-fan-ctrl
v2:
*Separated code into two files to keep size down: gpio-gxp.c and
gpio-gxp-pl.c
*Fixed Kconfig indentation as well as add new entry for gpio-gxp-pl
*Removed use of linux/of.h and linux/of_device.h
*Added mod_devicetable.h and property.h
*Fixed indentation of defines and uses consistent number of digits
*Corrected defines with improper GPIO_ namespace.
*For masks now use BIT()
*Added comment for PLREG offsets
*Move gpio_chip to be first in structure
*Calculate offset for high and low byte GPIO reads instead of having
H(High) and L(Low) letters added to the variables.
*Removed repeditive use of "? 1 : 0"
*Switched to handle_bad_irq()
*Removed improper bailout on gpiochip_add_data
*Used GENMASK to arm interrupts
*Removed use of of_match_device
*fixed sizeof in devm_kzalloc
*Added COMPILE_TEST to Kconfig
*Added dev_err_probe
*Removed unecessary parent and compatible checks
---
drivers/gpio/Kconfig | 9 +
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-gxp.c | 573 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 583 insertions(+)
create mode 100644 drivers/gpio/gpio-gxp.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 13be729710f2..fa0c9fdbb50c 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -1235,6 +1235,15 @@ config HTC_EGPIO
several HTC phones. It provides basic support for input
pins, output pins, and IRQs.

+config GPIO_GXP
+ tristate "GXP GPIO support"
+ depends on ARCH_HPE_GXP || COMPILE_TEST
+ select GPIOLIB_IRQCHIP
+ help
+ Say Y here to support GXP GPIO controllers. It provides
+ support for the multiple GPIO interfaces available to be
+ available to the Host.
+
config GPIO_JANZ_TTL
tristate "Janz VMOD-TTL Digital IO Module"
depends on MFD_JANZ_CMODIO
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index c048ba003367..a7ce0ab097aa 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -63,6 +63,7 @@ obj-$(CONFIG_GPIO_FTGPIO010) += gpio-ftgpio010.o
obj-$(CONFIG_GPIO_GE_FPGA) += gpio-ge.o
obj-$(CONFIG_GPIO_GPIO_MM) += gpio-gpio-mm.o
obj-$(CONFIG_GPIO_GRGPIO) += gpio-grgpio.o
+obj-$(CONFIG_GPIO_GXP) += gpio-gxp.o
obj-$(CONFIG_GPIO_GW_PLD) += gpio-gw-pld.o
obj-$(CONFIG_GPIO_HISI) += gpio-hisi.o
obj-$(CONFIG_GPIO_HLWD) += gpio-hlwd.o
diff --git a/drivers/gpio/gpio-gxp.c b/drivers/gpio/gpio-gxp.c
new file mode 100644
index 000000000000..4fe086137e86
--- /dev/null
+++ b/drivers/gpio/gpio-gxp.c
@@ -0,0 +1,573 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2023 Hewlett-Packard Enterprise Development Company, L.P. */
+
+#include <linux/gpio/driver.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+
+#define GPIDAT 0x040
+#define GPODAT 0x0b0
+#define GPODAT2 0x0f8
+#define GPOOWN 0x110
+#define GPOOWN2 0x118
+#define ASR_OFS 0x05c
+#define VUHC_OFS 0x064
+
+#define GXP_GPIO_DIR_OUT 0
+#define GXP_GPIO_DIR_IN 1
+
+#define PGOOD_MASK BIT(0)
+
+struct gxp_gpio_drvdata {
+ struct gpio_chip chip;
+ struct regmap *csm_map;
+ void __iomem *fn2_vbtn;
+ struct regmap *fn2_stat;
+ struct regmap *vuhc0_map;
+ int irq;
+};
+
+/*
+ * Note: Instead of definining all PINs here are the select few that
+ * are specifically defined in DTS and offsets are used here.
+ */
+enum gxp_gpio_pn {
+ RESET = 192,
+ VPBTN = 210, /* aka POWER_OK */
+ PGOOD = 211, /* aka PS_PWROK */
+ PERST = 212, /* aka PCIERST */
+ POST_COMPLETE = 213,
+};
+
+static int gxp_gpio_csm_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct gxp_gpio_drvdata *drvdata = dev_get_drvdata(chip->parent);
+ int ret = 0;
+ unsigned int reg_offset;
+ unsigned int reg_mask;
+
+ switch (offset) {
+ case 0 ... 31:
+ reg_offset = GPIDAT;
+ reg_mask = BIT(offset);
+ break;
+ case 32 ... 63:
+ reg_offset = GPIDAT + 0x20;
+ reg_mask = BIT(offset - 32);
+ break;
+ case 64 ... 95:
+ reg_offset = GPODAT;
+ reg_mask = BIT(offset - 64);
+ break;
+ case 96 ... 127:
+ reg_offset = GPODAT + 0x04;
+ reg_mask = BIT(offset - 96);
+ break;
+ case 128 ... 159:
+ reg_offset = GPODAT2;
+ reg_mask = BIT(offset - 128);
+ break;
+ case 160 ... 191:
+ reg_offset = GPODAT2 + 0x04;
+ reg_mask = BIT(offset - 160);
+ break;
+ case RESET:
+ /* SW_RESET */
+ reg_offset = ASR_OFS;
+ reg_mask = BIT(15);
+ break;
+ default:
+ break;
+ }
+
+ regmap_read(drvdata->csm_map, reg_offset, &ret);
+ ret = (ret & reg_mask) ? 1 : 0;
+
+ return ret;
+}
+
+static void gxp_gpio_csm_set(struct gpio_chip *chip, unsigned int offset,
+ int value)
+{
+ struct gxp_gpio_drvdata *drvdata = dev_get_drvdata(chip->parent);
+ u32 tmp;
+
+ switch (offset) {
+ case 64 ... 95:
+ /* Keep ownership setting */
+ regmap_read(drvdata->csm_map, GPOOWN, &tmp);
+ tmp = (tmp & BIT(offset - 64)) ? 1 : 0;
+
+ regmap_update_bits(drvdata->csm_map, GPOOWN,
+ BIT(offset - 64), BIT(offset - 64));
+ regmap_update_bits(drvdata->csm_map, GPODAT,
+ BIT(offset - 64), value ? BIT(offset - 64) : 0);
+
+ /* Restore ownership setting */
+ regmap_update_bits(drvdata->csm_map, GPOOWN,
+ BIT(offset - 64), tmp ? BIT(offset - 64) : 0);
+ break;
+ case 96 ... 127:
+ /* Keep ownership setting */
+ regmap_read(drvdata->csm_map, GPOOWN + 0x04, &tmp);
+ tmp = (tmp & BIT(offset - 96)) ? 1 : 0;
+
+ regmap_update_bits(drvdata->csm_map, GPOOWN + 0x04,
+ BIT(offset - 96), BIT(offset - 96));
+ regmap_update_bits(drvdata->csm_map, GPODAT + 0x04,
+ BIT(offset - 96), value ? BIT(offset - 96) : 0);
+
+ /* Restore ownership setting */
+ regmap_update_bits(drvdata->csm_map, GPOOWN + 0x04,
+ BIT(offset - 96), tmp ? BIT(offset - 96) : 0);
+ break;
+ case 128 ... 159:
+ /* Keep ownership setting */
+ regmap_read(drvdata->csm_map, GPOOWN2, &tmp);
+ tmp = (tmp & BIT(offset - 128)) ? 1 : 0;
+
+ regmap_update_bits(drvdata->csm_map, GPOOWN2,
+ BIT(offset - 128), BIT(offset - 128));
+ regmap_update_bits(drvdata->csm_map, GPODAT2,
+ BIT(offset - 128), value ? BIT(offset - 128) : 0);
+
+ /* Restore ownership setting */
+ regmap_update_bits(drvdata->csm_map, GPOOWN2,
+ BIT(offset - 128), tmp ? BIT(offset - 128) : 0);
+ break;
+ case 160 ... 191:
+ /* Keep ownership setting */
+ regmap_read(drvdata->csm_map, GPOOWN2 + 0x04, &tmp);
+ tmp = (tmp & BIT(offset - 160)) ? 1 : 0;
+
+ regmap_update_bits(drvdata->csm_map, GPOOWN2 + 0x04,
+ BIT(offset - 160), BIT(offset - 160));
+ regmap_update_bits(drvdata->csm_map, GPODAT2 + 0x04,
+ BIT(offset - 160), value ? BIT(offset - 160) : 0);
+
+ /* Restore ownership setting */
+ regmap_update_bits(drvdata->csm_map, GPOOWN2 + 0x04,
+ BIT(offset - 160), tmp ? BIT(offset - 160) : 0);
+ break;
+ case 192:
+ if (value) {
+ regmap_update_bits(drvdata->csm_map, ASR_OFS,
+ BIT(0), BIT(0));
+ regmap_update_bits(drvdata->csm_map, ASR_OFS,
+ BIT(15), BIT(15));
+ } else {
+ regmap_update_bits(drvdata->csm_map, ASR_OFS,
+ BIT(15), 0);
+ }
+ break;
+ default:
+ break;
+ }
+}
+
+static int gxp_gpio_csm_get_direction(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ switch (offset) {
+ case 0 ... 63:
+ return GXP_GPIO_DIR_IN;
+ case 64 ... 191:
+ return GXP_GPIO_DIR_OUT;
+ case 192 ... 193:
+ return GXP_GPIO_DIR_OUT;
+ case 194:
+ return GXP_GPIO_DIR_IN;
+ default:
+ return -ENOTSUPP;
+ }
+}
+
+static int gxp_gpio_csm_direction_input(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ switch (offset) {
+ case 0 ... 63:
+ return 0;
+ case 194:
+ return 0;
+ default:
+ return -ENOTSUPP;
+ }
+}
+
+static int gxp_gpio_csm_direction_output(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ switch (offset) {
+ case 64 ... 191:
+ case 192 ... 193:
+ gxp_gpio_csm_set(chip, offset, value);
+ return 0;
+ default:
+ return -ENOTSUPP;
+ }
+}
+
+static int gxp_gpio_vuhc_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct gxp_gpio_drvdata *drvdata = dev_get_drvdata(chip->parent);
+ unsigned int val;
+ int ret = 0;
+
+ if (offset < 8) {
+ regmap_read(drvdata->vuhc0_map, VUHC_OFS + 4 * offset, &val);
+ ret = (val & BIT(13)) ? 1 : 0;
+ }
+
+ return ret;
+}
+
+static void gxp_gpio_vuhc_set(struct gpio_chip *chip, unsigned int offset,
+ int value)
+{
+ /* Currently we are not supporting setting of these values yet */
+ switch (offset) {
+ default:
+ break;
+ }
+}
+
+static int gxp_gpio_vuhc_get_direction(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ switch (offset) {
+ case 0:
+ case 1:
+ case 2:
+ return GXP_GPIO_DIR_IN;
+ default:
+ return -ENOTSUPP;
+ }
+}
+
+static int gxp_gpio_vuhc_direction_input(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ switch (offset) {
+ case 0:
+ case 1:
+ case 2:
+ return 0;
+ default:
+ return -ENOTSUPP;
+ }
+}
+
+static int gxp_gpio_vuhc_direction_output(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ switch (offset) {
+ default:
+ return -ENOTSUPP;
+ }
+}
+
+static int gxp_gpio_fn2_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct gxp_gpio_drvdata *drvdata = dev_get_drvdata(chip->parent);
+ unsigned int val;
+ int ret = 0;
+ unsigned int reg_mask;
+
+ switch (offset) {
+ case PGOOD:
+ regmap_read(drvdata->fn2_stat, 0, &val);
+ reg_mask = BIT(24);
+
+ break;
+ case PERST:
+ regmap_read(drvdata->fn2_stat, 0, &val);
+ reg_mask = BIT(25);
+
+ break;
+ default:
+ return -ENOTSUPP;
+ }
+
+ regmap_read(drvdata->fn2_stat, 0, &val);
+ ret = (val & reg_mask);
+ /* Return either 1 or 0 */
+ return ret ? 1 : 0;
+}
+
+static void gxp_gpio_fn2_set(struct gpio_chip *chip, unsigned int offset,
+ int value)
+{
+ struct gxp_gpio_drvdata *drvdata = dev_get_drvdata(chip->parent);
+
+ switch (offset) {
+ case VPBTN:
+ writeb(1, drvdata->fn2_vbtn);
+ break;
+ default:
+ break;
+ }
+}
+
+static int gxp_gpio_fn2_get_direction(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ switch (offset) {
+ case VPBTN:
+ return GXP_GPIO_DIR_OUT;
+ default:
+ return GXP_GPIO_DIR_IN;
+ }
+}
+
+static int gxp_gpio_fn2_direction_input(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ switch (offset) {
+ case PGOOD:
+ case PERST:
+ case POST_COMPLETE:
+ return 0;
+ default:
+ return -ENOTSUPP;
+ }
+}
+
+static int gxp_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+ if (offset < 200)
+ return gxp_gpio_csm_get(chip, offset);
+ else if (offset >= 200 && offset < 210)
+ return gxp_gpio_vuhc_get(chip, offset - 200);
+ else if (offset >= 210)
+ return gxp_gpio_fn2_get(chip, offset);
+
+ return 0;
+}
+
+static void gxp_gpio_set(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ if (offset < 200)
+ gxp_gpio_csm_set(chip, offset, value);
+ else if (offset >= 200 && offset < 210)
+ gxp_gpio_vuhc_set(chip, offset - 200, value);
+ else if (offset >= 210)
+ gxp_gpio_fn2_set(chip, offset, value);
+}
+
+static int gxp_gpio_get_direction(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ if (offset < 200)
+ return gxp_gpio_csm_get_direction(chip, offset);
+ else if (offset >= 200 && offset < 210)
+ return gxp_gpio_vuhc_get_direction(chip, offset - 200);
+ else if (offset >= 210)
+ return gxp_gpio_fn2_get_direction(chip, offset);
+
+ return 0;
+}
+
+static int gxp_gpio_direction_input(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ if (offset < 200)
+ return gxp_gpio_csm_direction_input(chip, offset);
+ else if (offset >= 200 && offset < 210)
+ return gxp_gpio_vuhc_direction_input(chip, offset - 200);
+ else if (offset >= 210)
+ return gxp_gpio_fn2_direction_input(chip, offset);
+
+ return 0;
+}
+
+static int gxp_gpio_direction_output(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ if (offset < 200)
+ return gxp_gpio_csm_direction_output(chip, offset, value);
+ else if (offset >= 200 && offset < 210)
+ return gxp_gpio_vuhc_direction_output(chip, offset - 200, value);
+
+ return 0;
+}
+
+static const struct regmap_config gxp_regmap_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .name = "gxp",
+};
+
+static struct regmap *gxp_gpio_init_regmap(struct platform_device *pdev,
+ char *reg_name)
+{
+ void __iomem *base;
+
+ base = devm_platform_ioremap_resource_byname(pdev, reg_name);
+ if (IS_ERR(base))
+ return ERR_CAST(base);
+
+ return devm_regmap_init_mmio(&pdev->dev, base, &gxp_regmap_config);
+}
+
+static void gxp_gpio_fn2_irq_ack(struct irq_data *d)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
+ struct gxp_gpio_drvdata *drvdata = dev_get_drvdata(chip->parent);
+ unsigned int val;
+
+ /* Read latched interrupt */
+ regmap_read(drvdata->fn2_stat, 0, &val);
+ /* Clear latched interrupt */
+ regmap_update_bits(drvdata->fn2_stat, 0,
+ GENMASK(15, 0), GENMASK(15, 0));
+}
+
+#define FN2_SEVMASK BIT(2)
+static void gxp_gpio_fn2_irq_set_mask(struct irq_data *d, bool set)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
+ struct gxp_gpio_drvdata *drvdata = dev_get_drvdata(chip->parent);
+
+ regmap_update_bits(drvdata->fn2_stat, FN2_SEVMASK,
+ BIT(0), set ? BIT(0) : 0);
+}
+
+static void gxp_gpio_fn2_irq_mask(struct irq_data *d)
+{
+ gxp_gpio_fn2_irq_set_mask(d, false);
+}
+
+static void gxp_gpio_fn2_irq_unmask(struct irq_data *d)
+{
+ gxp_gpio_fn2_irq_set_mask(d, true);
+}
+
+static int gxp_gpio_fn2_set_type(struct irq_data *d, unsigned int type)
+{
+ if (type & IRQ_TYPE_LEVEL_MASK)
+ irq_set_handler_locked(d, handle_level_irq);
+ else
+ irq_set_handler_locked(d, handle_edge_irq);
+
+ return 0;
+}
+
+static irqreturn_t gxp_gpio_fn2_irq_handle(int irq, void *_drvdata)
+{
+ struct gxp_gpio_drvdata *drvdata = (struct gxp_gpio_drvdata *)_drvdata;
+ unsigned int val;
+
+ regmap_read(drvdata->fn2_stat, 0, &val);
+
+ if (val & PGOOD_MASK)
+ generic_handle_domain_irq(drvdata->chip.irq.domain, PGOOD);
+
+ return IRQ_HANDLED;
+}
+
+static const struct irq_chip gxp_gpio_irqchip = {
+ .name = "gxp_fn2",
+ .irq_ack = gxp_gpio_fn2_irq_ack,
+ .irq_mask = gxp_gpio_fn2_irq_mask,
+ .irq_unmask = gxp_gpio_fn2_irq_unmask,
+ .irq_set_type = gxp_gpio_fn2_set_type,
+ .flags = IRQCHIP_IMMUTABLE,
+};
+
+static const struct gpio_chip common_chip_template = {
+ .label = "gxp_gpio",
+ .owner = THIS_MODULE,
+ .get = gxp_gpio_get,
+ .set = gxp_gpio_set,
+ .get_direction = gxp_gpio_get_direction,
+ .direction_input = gxp_gpio_direction_input,
+ .direction_output = gxp_gpio_direction_output,
+ .base = 0,
+};
+
+static const struct of_device_id gxp_gpio_of_match[] = {
+ { .compatible = "hpe,gxp-gpio" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, gxp_gpio_of_match);
+
+static int gxp_gpio_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct gxp_gpio_drvdata *drvdata;
+ struct gpio_irq_chip *girq;
+
+ drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
+ if (!drvdata)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, drvdata);
+
+ drvdata->csm_map = gxp_gpio_init_regmap(pdev, "csm");
+ if (IS_ERR(drvdata->csm_map))
+ return dev_err_probe(&pdev->dev, PTR_ERR(drvdata->csm_map),
+ "failed to map csm_handle\n");
+
+ drvdata->fn2_vbtn = devm_platform_ioremap_resource_byname(pdev, "fn2-vbtn");
+ if (IS_ERR(drvdata->fn2_vbtn))
+ return dev_err_probe(&pdev->dev, PTR_ERR(drvdata->fn2_vbtn),
+ "failed to map fn2_vbtn\n");
+
+ drvdata->fn2_stat = gxp_gpio_init_regmap(pdev, "fn2-stat");
+ if (IS_ERR(drvdata->fn2_stat))
+ return dev_err_probe(&pdev->dev, PTR_ERR(drvdata->fn2_stat),
+ "failed to map fn2_stat\n");
+
+ drvdata->vuhc0_map = gxp_gpio_init_regmap(pdev, "vuhc");
+ if (IS_ERR(drvdata->vuhc0_map))
+ return dev_err_probe(&pdev->dev, PTR_ERR(drvdata->vuhc0_map),
+ "failed to map vuhc0_map\n");
+
+ girq = &drvdata->chip.irq;
+ gpio_irq_chip_set_chip(girq, &gxp_gpio_irqchip);
+ girq->parent_handler = NULL;
+ girq->num_parents = 0;
+ girq->parents = NULL;
+ girq->default_type = IRQ_TYPE_NONE;
+ girq->handler = handle_bad_irq;
+
+ ret = platform_get_irq(pdev, 0);
+ if (ret < 0)
+ return ret;
+
+ drvdata->irq = ret;
+
+ ret = devm_request_irq(&pdev->dev, drvdata->irq, gxp_gpio_fn2_irq_handle,
+ IRQF_SHARED, "gxp-fn2", drvdata);
+ if (ret < 0)
+ return ret;
+
+ drvdata->chip = common_chip_template;
+ drvdata->chip.ngpio = 220;
+
+ drvdata->chip.parent = &pdev->dev;
+
+ return devm_gpiochip_add_data(&pdev->dev, &drvdata->chip, NULL);
+}
+
+static struct platform_driver gxp_gpio_driver = {
+ .driver = {
+ .name = "gxp-gpio",
+ .of_match_table = gxp_gpio_of_match,
+ },
+ .probe = gxp_gpio_probe,
+};
+module_platform_driver(gxp_gpio_driver);
+
+MODULE_AUTHOR("Nick Hawkins <nick.hawkins@xxxxxxx>");
+MODULE_DESCRIPTION("GPIO interface for GXP");
+MODULE_LICENSE("GPL");
--
2.17.1