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| author | Rob Herring (Arm) <robh@kernel.org> | 2026-08-31 14:43:51 -0500 |
|---|---|---|
| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2026-09-13 18:17:31 -0700 |
| commit | 55fc280e951ab2b39f3dcb640edc1b1eebc6d173 (patch) | |
| tree | f0b5f37b42fc13b9908a31b657c646b024231cdd /drivers/clocksource/armv7m_systick.c | |
| download | linux-stable-55fc280e951ab2b39f3dcb640edc1b1eebc6d173.tar.gz linux-stable-55fc280e951ab2b39f3dcb640edc1b1eebc6d173.zip | |
Input: tsc2007 - read "ti,poll-period" as u32grafted
The "ti,poll-period" property is documented as a normal uint32 cell.
The driver used a u64 helper, which makes the helper type disagree with
the schema even though the stored value is still small.
Read "ti,poll-period" with the u32 helper matching the documented DT
cell size.
Assisted-by: Codex:gpt-5-5
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20260831194352.1185860-1-robh@kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'drivers/clocksource/armv7m_systick.c')
| -rw-r--r-- | drivers/clocksource/armv7m_systick.c | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/drivers/clocksource/armv7m_systick.c b/drivers/clocksource/armv7m_systick.c new file mode 100644 index 000000000..7e7807448 --- /dev/null +++ b/drivers/clocksource/armv7m_systick.c @@ -0,0 +1,86 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) Maxime Coquelin 2015 + * Author: Maxime Coquelin <mcoquelin.stm32@gmail.com> + */ + +#include <linux/kernel.h> +#include <linux/clocksource.h> +#include <linux/clockchips.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/clk.h> +#include <linux/bitops.h> + +#define SYST_CSR 0x00 +#define SYST_RVR 0x04 +#define SYST_CVR 0x08 +#define SYST_CALIB 0x0c + +#define SYST_CSR_ENABLE BIT(0) + +#define SYSTICK_LOAD_RELOAD_MASK 0x00FFFFFF + +static int __init system_timer_of_register(struct device_node *np) +{ + struct clk *clk = NULL; + void __iomem *base; + u32 rate; + int ret; + + base = of_iomap(np, 0); + if (!base) { + pr_warn("system-timer: invalid base address\n"); + return -ENXIO; + } + + ret = of_property_read_u32(np, "clock-frequency", &rate); + if (ret) { + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + goto out_unmap; + } + + ret = clk_prepare_enable(clk); + if (ret) + goto out_clk_put; + + rate = clk_get_rate(clk); + if (!rate) { + ret = -EINVAL; + goto out_clk_disable; + } + } + + writel_relaxed(SYSTICK_LOAD_RELOAD_MASK, base + SYST_RVR); + writel_relaxed(SYST_CSR_ENABLE, base + SYST_CSR); + + ret = clocksource_mmio_init(base + SYST_CVR, "arm_system_timer", rate, + 200, 24, clocksource_mmio_readl_down); + if (ret) { + pr_err("failed to init clocksource (%d)\n", ret); + if (clk) + goto out_clk_disable; + else + goto out_unmap; + } + + pr_info("ARM System timer initialized as clocksource\n"); + + return 0; + +out_clk_disable: + clk_disable_unprepare(clk); +out_clk_put: + clk_put(clk); +out_unmap: + iounmap(base); + pr_warn("ARM System timer register failed (%d)\n", ret); + + return ret; +} + +TIMER_OF_DECLARE(arm_systick, "arm,armv7m-systick", + system_timer_of_register); |
