[RFC PATCH v1 01/20] gpio: Add basic GPIO driver for Intel PMC Timed I/O device
From: lakshmi . sowjanya . d
Date: Tue Aug 24 2021 - 12:48:12 EST
From: Christopher Hall <christopher.s.hall@xxxxxxxxx>
The Intel PMC Timed I/O device provides GPIO-like functionality to
generate and capture I/O timestamped using ART
Several additional GPIO interfaces are needed to enable the device.
Add basic driver initialization, acpi_match_tables and register accessors.
Add entry for INTEL GPIO PMC TIO driver and the test drivers
gpio-event-gen.c and gpio-pwm-mon.c in the MAINTAINERS file.
Signed-off-by: Christopher Hall <christopher.s.hall@xxxxxxxxx>
Signed-off-by: Tamal Saha <tamal.saha@xxxxxxxxx>
Co-developed-by: Lakshmi Sowjanya D <lakshmi.sowjanya.d@xxxxxxxxx>
Signed-off-by: Lakshmi Sowjanya D <lakshmi.sowjanya.d@xxxxxxxxx>
Reviewed-by: Mark Gross <mgross@xxxxxxxxxxxxxxx>
---
MAINTAINERS | 7 ++
drivers/gpio/Kconfig | 11 ++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-intel-tio-pmc.c | 182 ++++++++++++++++++++++++++++++
4 files changed, 201 insertions(+)
create mode 100644 drivers/gpio/gpio-intel-tio-pmc.c
diff --git a/MAINTAINERS b/MAINTAINERS
index c6b8a720c0bc..1b61e80deeae 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9311,6 +9311,13 @@ F: drivers/gpio/gpio-pch.c
F: drivers/gpio/gpio-sch.c
F: drivers/gpio/gpio-sodaville.c
+INTEL GPIO PMC TIO
+M: Tamal Saha <tamal.saha@xxxxxxxxx>
+S: Supported
+F: drivers/gpio/gpio-intel-tio-pmc.c
+F: tools/gpio/gpio-event-gen.c
+F: tools/gpio/gpio-pwm-mon.c
+
INTEL GVT-g DRIVERS (Intel GPU Virtualization)
M: Zhenyu Wang <zhenyuw@xxxxxxxxxxxxxxx>
M: Zhi Wang <zhi.a.wang@xxxxxxxxx>
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index fab571016adf..962a92db09ba 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -794,6 +794,17 @@ config GPIO_IDT3243X
To compile this driver as a module, choose M here: the module will
be called gpio-idt3243x.
+config GPIO_INTEL_PMC_TIO
+ tristate "Intel PMC Time-Aware GPIO"
+ depends on X86
+ select GPIO_GENERIC
+ help
+ This driver adds support for Intel PMC Timed-Aware GPIO (TGPIO)
+ controller. The device clock used to drive TGPIO logic is the
+ Always Running Timer (ART).
+
+ Say yes here to build support for PMC TGPIO Driver.
+
endmenu
menu "Port-mapped I/O GPIO drivers"
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 32a32659866a..59bb4e756382 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -183,3 +183,4 @@ obj-$(CONFIG_GPIO_XRA1403) += gpio-xra1403.o
obj-$(CONFIG_GPIO_XTENSA) += gpio-xtensa.o
obj-$(CONFIG_GPIO_ZEVIO) += gpio-zevio.o
obj-$(CONFIG_GPIO_ZYNQ) += gpio-zynq.o
+obj-$(CONFIG_GPIO_INTEL_PMC_TIO) += gpio-intel-tio-pmc.o
diff --git a/drivers/gpio/gpio-intel-tio-pmc.c b/drivers/gpio/gpio-intel-tio-pmc.c
new file mode 100644
index 000000000000..e6436b56ebea
--- /dev/null
+++ b/drivers/gpio/gpio-intel-tio-pmc.c
@@ -0,0 +1,182 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel Time-Aware GPIO Controller Driver
+ * Copyright (C) 2021 Intel Corporation
+ */
+
+#include <linux/acpi.h>
+#include <linux/debugfs.h>
+#include <linux/gpio/driver.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <uapi/linux/gpio.h>
+
+#define TGPIOCTL 0x00
+#define TGPIOCOMPV31_0 0x10
+#define TGPIOCOMPV63_32 0x14
+#define TGPIOPIV31_0 0x18
+#define TGPIOPIV63_32 0x1c
+#define TGPIOTCV31_0 0x20
+#define TGPIOTCV63_32 0x24 /* Not used */
+#define TGPIOECCV31_0 0x28
+#define TGPIOECCV63_32 0x2c
+#define TGPIOEC31_0 0x30
+#define TGPIOEC63_32 0x34
+
+/* Control Register */
+#define TGPIOCTL_EN BIT(0)
+#define TGPIOCTL_DIR BIT(1)
+#define TGPIOCTL_EP GENMASK(3, 2)
+#define TGPIOCTL_EP_RISING_EDGE (0 << 2)
+#define TGPIOCTL_EP_FALLING_EDGE BIT(2)
+#define TGPIOCTL_EP_TOGGLE_EDGE BIT(3)
+#define TGPIOCTL_PM BIT(4)
+
+#define DRIVER_NAME "intel-pmc-tio"
+
+struct intel_pmc_tio_chip {
+ struct gpio_chip gch;
+ struct platform_device *pdev;
+ struct dentry *root;
+ struct debugfs_regset32 *regset;
+ void __iomem *base;
+};
+
+static const struct debugfs_reg32 intel_pmc_tio_regs[] = {
+ {
+ .name = "TGPIOCTL",
+ .offset = TGPIOCTL
+ },
+ {
+ .name = "TGPIOCOMPV31_0",
+ .offset = TGPIOCOMPV31_0
+ },
+ {
+ .name = "TGPIOCOMPV63_32",
+ .offset = TGPIOCOMPV63_32
+ },
+ {
+ .name = "TGPIOPIV31_0",
+ .offset = TGPIOPIV31_0
+ },
+ {
+ .name = "TGPIOPIV63_32",
+ .offset = TGPIOPIV63_32
+ },
+ {
+ .name = "TGPIOECCV31_0",
+ .offset = TGPIOECCV31_0
+ },
+ {
+ .name = "TGPIOECCV63_32",
+ .offset = TGPIOECCV63_32
+ },
+ {
+ .name = "TGPIOEC31_0",
+ .offset = TGPIOEC31_0
+ },
+ {
+ .name = "TGPIOEC63_32",
+ .offset = TGPIOEC63_32
+ },
+};
+
+static int intel_pmc_tio_probe(struct platform_device *pdev)
+{
+ struct intel_pmc_tio_chip *tio;
+ int err;
+
+ tio = devm_kzalloc(&pdev->dev, sizeof(*tio), GFP_KERNEL);
+ if (!tio)
+ return -ENOMEM;
+ tio->pdev = pdev;
+
+ tio->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(tio->base))
+ return PTR_ERR(tio->base);
+
+ tio->regset = devm_kzalloc
+ (&pdev->dev, sizeof(*tio->regset), GFP_KERNEL);
+ if (!tio->regset)
+ return -ENOMEM;
+
+ tio->regset->regs = intel_pmc_tio_regs;
+ tio->regset->nregs = ARRAY_SIZE(intel_pmc_tio_regs);
+ tio->regset->base = tio->base;
+
+ tio->root = debugfs_create_dir(pdev->name, NULL);
+ if (IS_ERR(tio->root))
+ return PTR_ERR(tio->root);
+
+ debugfs_create_regset32("regdump", 0444, tio->root, tio->regset);
+
+ tio->gch.label = pdev->name;
+ tio->gch.ngpio = 0;
+ tio->gch.base = -1;
+
+ platform_set_drvdata(pdev, tio);
+
+ err = devm_gpiochip_add_data(&pdev->dev, &tio->gch, tio);
+ if (err < 0)
+ goto out_recurse_remove_tio_root;
+
+ return 0;
+
+out_recurse_remove_tio_root:
+ debugfs_remove_recursive(tio->root);
+
+ return err;
+}
+
+static int intel_pmc_tio_remove(struct platform_device *pdev)
+{
+ struct intel_pmc_tio_chip *tio;
+
+ tio = platform_get_drvdata(pdev);
+ if (!tio)
+ return -ENODEV;
+
+ debugfs_remove_recursive(tio->root);
+
+ return 0;
+}
+
+static const struct acpi_device_id intel_pmc_tio_acpi_match[] = {
+ { "INTC1021", 0 }, /* EHL */
+ { "INTC1022", 0 }, /* EHL */
+ { "INTC1023", 0 }, /* TGL */
+ { "INTC1024", 0 }, /* TGL */
+ { }
+};
+
+static struct platform_driver intel_pmc_tio_driver = {
+ .probe = intel_pmc_tio_probe,
+ .remove = intel_pmc_tio_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .acpi_match_table = intel_pmc_tio_acpi_match,
+ },
+};
+
+static int intel_pmc_tio_init(void)
+{
+ /* To ensure ART to TSC conversion is correct */
+ if (!boot_cpu_has(X86_FEATURE_TSC_KNOWN_FREQ))
+ return -ENXIO;
+
+ return platform_driver_register(&intel_pmc_tio_driver);
+}
+
+static void intel_pmc_tio_exit(void)
+{
+ platform_driver_unregister(&intel_pmc_tio_driver);
+}
+
+module_init(intel_pmc_tio_init);
+module_exit(intel_pmc_tio_exit);
+
+MODULE_AUTHOR("Christopher Hall <christopher.s.hall@xxxxxxxxx>");
+MODULE_AUTHOR("Tamal Saha <tamal.saha@xxxxxxxxx>");
+MODULE_AUTHOR("Lakshmi Sowjanya D <lakshmi.sowjanya.d@xxxxxxxxx>");
+MODULE_DESCRIPTION("Intel PMC Time-Aware GPIO Controller Driver");
+MODULE_LICENSE("GPL v2");
--
2.17.1