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authorArnd Bergmann <arnd@arndb.de>2022-05-27 16:52:46 +0300
committerArnd Bergmann <arnd@arndb.de>2022-05-27 16:55:37 +0300
commit3e11194631275937bc40da49b98aa1a74dd1ee67 (patch)
treea6fde5b67ca56f22fb1688b5ec2c575561b10885 /drivers/clocksource
parent16477cdfefdb494235a675cc80563d736991d833 (diff)
parent2fa1533f79d3fa69cbd65605f6d57adbb2633079 (diff)
downloadlinux-3e11194631275937bc40da49b98aa1a74dd1ee67.tar.xz
Merge branch 'hpe/gxp-soc' into arm/late
Patch series from Nick Hawkins: "The GXP is the HPE BMC SoC that is used in the majority of HPE current generation servers. Traditionally the asic will last multiple generations of server before being replaced. Info about SoC: HPE GXP is the name of the HPE Soc. This SoC is used to implement many BMC features at HPE. It supports ARMv7 architecture based on the Cortex A9 core. It is capable of using an AXI bus to which a memory controller is attached. It has multiple SPI interfaces to connect boot flash and BIOS flash. It uses a 10/100/1000 MAC for network connectivity. It has multiple i2c engines to drive connectivity with a host infrastructure. The initial patches enable the watchdog and timer enabling the host to be able to boot." * hpe/gxp-soc: MAINTAINERS: Introduce HPE GXP Architecture ARM: dts: Introduce HPE GXP Device tree dt-bindings: arm: hpe: add GXP Support dt-bindings: timer: hpe,gxp-timer: Add HPE GXP Timer and Watchdog clocksource/drivers/timer-gxp: Add HPE GXP Timer watchdog: hpe-wdt: Introduce HPE GXP Watchdog ARM: configs: multi_v7_defconfig: Add HPE GXP ARCH ARM: hpe: Introduce the HPE GXP architecture Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'drivers/clocksource')
-rw-r--r--drivers/clocksource/Kconfig8
-rw-r--r--drivers/clocksource/Makefile1
-rw-r--r--drivers/clocksource/timer-gxp.c209
3 files changed, 218 insertions, 0 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index fe3f05dfafd9..b5c86d37caa9 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -597,6 +597,14 @@ config CLKSRC_ST_LPC
Enable this option to use the Low Power controller timer
as clocksource.
+config GXP_TIMER
+ bool "GXP timer driver" if COMPILE_TEST && !ARCH_HPE
+ default ARCH_HPE
+ select TIMER_OF if OF
+ help
+ Provides a driver for the timer control found on HPE
+ GXP SOCs. This is required for all GXP SOCs.
+
config RISCV_TIMER
bool "Timer for the RISC-V platform" if COMPILE_TEST
depends on GENERIC_SCHED_CLOCK && RISCV && RISCV_SBI
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 833cfb7a96c1..6ca640019e10 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -86,3 +86,4 @@ obj-$(CONFIG_HYPERV_TIMER) += hyperv_timer.o
obj-$(CONFIG_MICROCHIP_PIT64B) += timer-microchip-pit64b.o
obj-$(CONFIG_MSC313E_TIMER) += timer-msc313e.o
obj-$(CONFIG_GOLDFISH_TIMER) += timer-goldfish.o
+obj-$(CONFIG_GXP_TIMER) += timer-gxp.o
diff --git a/drivers/clocksource/timer-gxp.c b/drivers/clocksource/timer-gxp.c
new file mode 100644
index 000000000000..8b38b3212388
--- /dev/null
+++ b/drivers/clocksource/timer-gxp.c
@@ -0,0 +1,209 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2022 Hewlett-Packard Enterprise Development Company, L.P. */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/sched_clock.h>
+
+#define TIMER0_FREQ 1000000
+#define GXP_TIMER_CNT_OFS 0x00
+#define GXP_TIMESTAMP_OFS 0x08
+#define GXP_TIMER_CTRL_OFS 0x14
+
+/* TCS Stands for Timer Control/Status: these are masks to be used in */
+/* the Timer Count Registers */
+#define MASK_TCS_ENABLE 0x01
+#define MASK_TCS_PERIOD 0x02
+#define MASK_TCS_RELOAD 0x04
+#define MASK_TCS_TC 0x80
+
+struct gxp_timer {
+ void __iomem *counter;
+ void __iomem *control;
+ struct clock_event_device evt;
+};
+
+static struct gxp_timer *gxp_timer;
+
+static void __iomem *system_clock __ro_after_init;
+
+static inline struct gxp_timer *to_gxp_timer(struct clock_event_device *evt_dev)
+{
+ return container_of(evt_dev, struct gxp_timer, evt);
+}
+
+static u64 notrace gxp_sched_read(void)
+{
+ return readl_relaxed(system_clock);
+}
+
+static int gxp_time_set_next_event(unsigned long event, struct clock_event_device *evt_dev)
+{
+ struct gxp_timer *timer = to_gxp_timer(evt_dev);
+
+ /* Stop counting and disable interrupt before updating */
+ writeb_relaxed(MASK_TCS_TC, timer->control);
+ writel_relaxed(event, timer->counter);
+ writeb_relaxed(MASK_TCS_TC | MASK_TCS_ENABLE, timer->control);
+
+ return 0;
+}
+
+static irqreturn_t gxp_timer_interrupt(int irq, void *dev_id)
+{
+ struct gxp_timer *timer = (struct gxp_timer *)dev_id;
+
+ if (!(readb_relaxed(timer->control) & MASK_TCS_TC))
+ return IRQ_NONE;
+
+ writeb_relaxed(MASK_TCS_TC, timer->control);
+
+ timer->evt.event_handler(&timer->evt);
+
+ return IRQ_HANDLED;
+}
+
+static int __init gxp_timer_init(struct device_node *node)
+{
+ void __iomem *base;
+ struct clk *clk;
+ u32 freq;
+ int ret, irq;
+
+ gxp_timer = kzalloc(sizeof(*gxp_timer), GFP_KERNEL);
+ if (!gxp_timer) {
+ ret = -ENOMEM;
+ pr_err("Can't allocate gxp_timer");
+ return ret;
+ }
+
+ clk = of_clk_get(node, 0);
+ if (IS_ERR(clk)) {
+ ret = (int)PTR_ERR(clk);
+ pr_err("%pOFn clock not found: %d\n", node, ret);
+ goto err_free;
+ }
+
+ ret = clk_prepare_enable(clk);
+ if (ret) {
+ pr_err("%pOFn clock enable failed: %d\n", node, ret);
+ goto err_clk_enable;
+ }
+
+ base = of_iomap(node, 0);
+ if (!base) {
+ ret = -ENXIO;
+ pr_err("Can't map timer base registers");
+ goto err_iomap;
+ }
+
+ /* Set the offsets to the clock register and timer registers */
+ gxp_timer->counter = base + GXP_TIMER_CNT_OFS;
+ gxp_timer->control = base + GXP_TIMER_CTRL_OFS;
+ system_clock = base + GXP_TIMESTAMP_OFS;
+
+ gxp_timer->evt.name = node->name;
+ gxp_timer->evt.rating = 300;
+ gxp_timer->evt.features = CLOCK_EVT_FEAT_ONESHOT;
+ gxp_timer->evt.set_next_event = gxp_time_set_next_event;
+ gxp_timer->evt.cpumask = cpumask_of(0);
+
+ irq = irq_of_parse_and_map(node, 0);
+ if (irq <= 0) {
+ ret = -EINVAL;
+ pr_err("GXP Timer Can't parse IRQ %d", irq);
+ goto err_exit;
+ }
+
+ freq = clk_get_rate(clk);
+
+ ret = clocksource_mmio_init(system_clock, node->name, freq,
+ 300, 32, clocksource_mmio_readl_up);
+ if (ret) {
+ pr_err("%pOFn init clocksource failed: %d", node, ret);
+ goto err_exit;
+ }
+
+ sched_clock_register(gxp_sched_read, 32, freq);
+
+ irq = irq_of_parse_and_map(node, 0);
+ if (irq <= 0) {
+ ret = -EINVAL;
+ pr_err("%pOFn Can't parse IRQ %d", node, irq);
+ goto err_exit;
+ }
+
+ clockevents_config_and_register(&gxp_timer->evt, TIMER0_FREQ,
+ 0xf, 0xffffffff);
+
+ ret = request_irq(irq, gxp_timer_interrupt, IRQF_TIMER | IRQF_SHARED,
+ node->name, gxp_timer);
+ if (ret) {
+ pr_err("%pOFn request_irq() failed: %d", node, ret);
+ goto err_exit;
+ }
+
+ pr_debug("gxp: system timer (irq = %d)\n", irq);
+ return 0;
+
+err_exit:
+ iounmap(base);
+err_iomap:
+ clk_disable_unprepare(clk);
+err_clk_enable:
+ clk_put(clk);
+err_free:
+ kfree(gxp_timer);
+ return ret;
+}
+
+/*
+ * This probe gets called after the timer is already up and running. This will create
+ * the watchdog device as a child since the registers are shared.
+ */
+
+static int gxp_timer_probe(struct platform_device *pdev)
+{
+ struct platform_device *gxp_watchdog_device;
+ struct device *dev = &pdev->dev;
+
+ if (!gxp_timer) {
+ pr_err("Gxp Timer not initialized, cannot create watchdog");
+ return -ENOMEM;
+ }
+
+ gxp_watchdog_device = platform_device_alloc("gxp-wdt", -1);
+ if (!gxp_watchdog_device) {
+ pr_err("Timer failed to allocate gxp-wdt");
+ return -ENOMEM;
+ }
+
+ /* Pass the base address (counter) as platform data and nothing else */
+ gxp_watchdog_device->dev.platform_data = gxp_timer->counter;
+ gxp_watchdog_device->dev.parent = dev;
+
+ return platform_device_add(gxp_watchdog_device);
+}
+
+static const struct of_device_id gxp_timer_of_match[] = {
+ { .compatible = "hpe,gxp-timer", },
+ {},
+};
+
+static struct platform_driver gxp_timer_driver = {
+ .probe = gxp_timer_probe,
+ .driver = {
+ .name = "gxp-timer",
+ .of_match_table = gxp_timer_of_match,
+ .suppress_bind_attrs = true,
+ },
+};
+
+builtin_platform_driver(gxp_timer_driver);
+
+TIMER_OF_DECLARE(gxp, "hpe,gxp-timer", gxp_timer_init);