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author | AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> | 2023-03-09 11:39:13 +0100 |
---|---|---|
committer | Daniel Lezcano <daniel.lezcano@linaro.org> | 2023-04-24 16:56:13 +0200 |
commit | 49d576ea72a4fa5be15717babfa308b70b2bc5a4 (patch) | |
tree | f62194a9bdf48728d850e7ff8558595513af9eec | |
parent | fd3f088f35f610a7ee3045b7d172b362342e43c6 (diff) | |
download | linux-49d576ea72a4fa5be15717babfa308b70b2bc5a4.tar.gz linux-49d576ea72a4fa5be15717babfa308b70b2bc5a4.tar.bz2 linux-49d576ea72a4fa5be15717babfa308b70b2bc5a4.zip |
clocksource/drivers/timer-mediatek: Split out CPUXGPT timers
On MediaTek platforms, CPUXGPT is the source for the AArch64 System
Timer, read through CNTVCT_EL0.
The handling for starting this timer ASAP was introduced in commit
327e93cf9a59 ("clocksource/drivers/timer-mediatek: Implement CPUXGPT timers")
which description also contains an important full explanation of the
reasons why this driver is necessary and cannot be a module.
In preparation for an eventual conversion of timer-mediatek to a
platform_driver that would be possibly built as a module, split out
the CPUXGPT timers driver to a new timer-mediatek-cpux.c driver.
This commit brings no functional changes.
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Walter Chang <walter.chang@mediatek.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230309103913.116775-1-angelogioacchino.delregno@collabora.com
-rw-r--r-- | drivers/clocksource/Kconfig | 9 | ||||
-rw-r--r-- | drivers/clocksource/Makefile | 1 | ||||
-rw-r--r-- | drivers/clocksource/timer-mediatek-cpux.c | 140 | ||||
-rw-r--r-- | drivers/clocksource/timer-mediatek.c | 114 |
4 files changed, 150 insertions, 114 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 5fc8f0e7fb38..526382dc7482 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -479,6 +479,15 @@ config MTK_TIMER help Support for Mediatek timer driver. +config MTK_CPUX_TIMER + bool "MediaTek CPUX timer driver" if COMPILE_TEST + depends on HAS_IOMEM + default ARCH_MEDIATEK + select TIMER_OF + select CLKSRC_MMIO + help + Support for MediaTek CPUXGPT timer driver. + config SPRD_TIMER bool "Spreadtrum timer driver" if EXPERT depends on HAS_IOMEM diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 64ab547de97b..f12d3987a960 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -51,6 +51,7 @@ obj-$(CONFIG_FSL_FTM_TIMER) += timer-fsl-ftm.o obj-$(CONFIG_VF_PIT_TIMER) += timer-vf-pit.o obj-$(CONFIG_CLKSRC_QCOM) += timer-qcom.o obj-$(CONFIG_MTK_TIMER) += timer-mediatek.o +obj-$(CONFIG_MTK_CPUX_TIMER) += timer-mediatek-cpux.o obj-$(CONFIG_CLKSRC_PISTACHIO) += timer-pistachio.o obj-$(CONFIG_CLKSRC_TI_32K) += timer-ti-32k.o obj-$(CONFIG_OXNAS_RPS_TIMER) += timer-oxnas-rps.o diff --git a/drivers/clocksource/timer-mediatek-cpux.c b/drivers/clocksource/timer-mediatek-cpux.c new file mode 100644 index 000000000000..a8e3df4c09fd --- /dev/null +++ b/drivers/clocksource/timer-mediatek-cpux.c @@ -0,0 +1,140 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * MediaTek SoCs CPUX General Purpose Timer handling + * + * Based on timer-mediatek.c: + * Copyright (C) 2014 Matthias Brugger <matthias.bgg@gmail.com> + * + * Copyright (C) 2022 Collabora Ltd. + * AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/clockchips.h> +#include <linux/clocksource.h> +#include <linux/interrupt.h> +#include <linux/irqreturn.h> +#include <linux/sched_clock.h> +#include <linux/slab.h> +#include "timer-of.h" + +#define TIMER_SYNC_TICKS 3 + +/* cpux mcusys wrapper */ +#define CPUX_CON_REG 0x0 +#define CPUX_IDX_REG 0x4 + +/* cpux */ +#define CPUX_IDX_GLOBAL_CTRL 0x0 + #define CPUX_ENABLE BIT(0) + #define CPUX_CLK_DIV_MASK GENMASK(10, 8) + #define CPUX_CLK_DIV1 BIT(8) + #define CPUX_CLK_DIV2 BIT(9) + #define CPUX_CLK_DIV4 BIT(10) +#define CPUX_IDX_GLOBAL_IRQ 0x30 + +static u32 mtk_cpux_readl(u32 reg_idx, struct timer_of *to) +{ + writel(reg_idx, timer_of_base(to) + CPUX_IDX_REG); + return readl(timer_of_base(to) + CPUX_CON_REG); +} + +static void mtk_cpux_writel(u32 val, u32 reg_idx, struct timer_of *to) +{ + writel(reg_idx, timer_of_base(to) + CPUX_IDX_REG); + writel(val, timer_of_base(to) + CPUX_CON_REG); +} + +static void mtk_cpux_set_irq(struct timer_of *to, bool enable) +{ + const unsigned long *irq_mask = cpumask_bits(cpu_possible_mask); + u32 val; + + val = mtk_cpux_readl(CPUX_IDX_GLOBAL_IRQ, to); + + if (enable) + val |= *irq_mask; + else + val &= ~(*irq_mask); + + mtk_cpux_writel(val, CPUX_IDX_GLOBAL_IRQ, to); +} + +static int mtk_cpux_clkevt_shutdown(struct clock_event_device *clkevt) +{ + /* Clear any irq */ + mtk_cpux_set_irq(to_timer_of(clkevt), false); + + /* + * Disabling CPUXGPT timer will crash the platform, especially + * if Trusted Firmware is using it (usually, for sleep states), + * so we only mask the IRQ and call it a day. + */ + return 0; +} + +static int mtk_cpux_clkevt_resume(struct clock_event_device *clkevt) +{ + mtk_cpux_set_irq(to_timer_of(clkevt), true); + return 0; +} + +static struct timer_of to = { + /* + * There are per-cpu interrupts for the CPUX General Purpose Timer + * but since this timer feeds the AArch64 System Timer we can rely + * on the CPU timer PPIs as well, so we don't declare TIMER_OF_IRQ. + */ + .flags = TIMER_OF_BASE | TIMER_OF_CLOCK, + + .clkevt = { + .name = "mtk-cpuxgpt", + .cpumask = cpu_possible_mask, + .rating = 10, + .set_state_shutdown = mtk_cpux_clkevt_shutdown, + .tick_resume = mtk_cpux_clkevt_resume, + }, +}; + +static int __init mtk_cpux_init(struct device_node *node) +{ + u32 freq, val; + int ret; + + /* If this fails, bad things are about to happen... */ + ret = timer_of_init(node, &to); + if (ret) { + WARN(1, "Cannot start CPUX timers.\n"); + return ret; + } + + /* + * Check if we're given a clock with the right frequency for this + * timer, otherwise warn but keep going with the setup anyway, as + * that makes it possible to still boot the kernel, even though + * it may not work correctly (random lockups, etc). + * The reason behind this is that having an early UART may not be + * possible for everyone and this gives a chance to retrieve kmsg + * for eventual debugging even on consumer devices. + */ + freq = timer_of_rate(&to); + if (freq > 13000000) + WARN(1, "Requested unsupported timer frequency %u\n", freq); + + /* Clock input is 26MHz, set DIV2 to achieve 13MHz clock */ + val = mtk_cpux_readl(CPUX_IDX_GLOBAL_CTRL, &to); + val &= ~CPUX_CLK_DIV_MASK; + val |= CPUX_CLK_DIV2; + mtk_cpux_writel(val, CPUX_IDX_GLOBAL_CTRL, &to); + + /* Enable all CPUXGPT timers */ + val = mtk_cpux_readl(CPUX_IDX_GLOBAL_CTRL, &to); + mtk_cpux_writel(val | CPUX_ENABLE, CPUX_IDX_GLOBAL_CTRL, &to); + + clockevents_config_and_register(&to.clkevt, timer_of_rate(&to), + TIMER_SYNC_TICKS, 0xffffffff); + + return 0; +} +TIMER_OF_DECLARE(mtk_mt6795, "mediatek,mt6795-systimer", mtk_cpux_init); diff --git a/drivers/clocksource/timer-mediatek.c b/drivers/clocksource/timer-mediatek.c index d5b29fd03ca2..7bcb4a3f26fb 100644 --- a/drivers/clocksource/timer-mediatek.c +++ b/drivers/clocksource/timer-mediatek.c @@ -22,19 +22,6 @@ #define TIMER_SYNC_TICKS (3) -/* cpux mcusys wrapper */ -#define CPUX_CON_REG 0x0 -#define CPUX_IDX_REG 0x4 - -/* cpux */ -#define CPUX_IDX_GLOBAL_CTRL 0x0 - #define CPUX_ENABLE BIT(0) - #define CPUX_CLK_DIV_MASK GENMASK(10, 8) - #define CPUX_CLK_DIV1 BIT(8) - #define CPUX_CLK_DIV2 BIT(9) - #define CPUX_CLK_DIV4 BIT(10) -#define CPUX_IDX_GLOBAL_IRQ 0x30 - /* gpt */ #define GPT_IRQ_EN_REG 0x00 #define GPT_IRQ_ENABLE(val) BIT((val) - 1) @@ -85,52 +72,6 @@ static void __iomem *gpt_sched_reg __read_mostly; -static u32 mtk_cpux_readl(u32 reg_idx, struct timer_of *to) -{ - writel(reg_idx, timer_of_base(to) + CPUX_IDX_REG); - return readl(timer_of_base(to) + CPUX_CON_REG); -} - -static void mtk_cpux_writel(u32 val, u32 reg_idx, struct timer_of *to) -{ - writel(reg_idx, timer_of_base(to) + CPUX_IDX_REG); - writel(val, timer_of_base(to) + CPUX_CON_REG); -} - -static void mtk_cpux_set_irq(struct timer_of *to, bool enable) -{ - const unsigned long *irq_mask = cpumask_bits(cpu_possible_mask); - u32 val; - - val = mtk_cpux_readl(CPUX_IDX_GLOBAL_IRQ, to); - - if (enable) - val |= *irq_mask; - else - val &= ~(*irq_mask); - - mtk_cpux_writel(val, CPUX_IDX_GLOBAL_IRQ, to); -} - -static int mtk_cpux_clkevt_shutdown(struct clock_event_device *clkevt) -{ - /* Clear any irq */ - mtk_cpux_set_irq(to_timer_of(clkevt), false); - - /* - * Disabling CPUXGPT timer will crash the platform, especially - * if Trusted Firmware is using it (usually, for sleep states), - * so we only mask the IRQ and call it a day. - */ - return 0; -} - -static int mtk_cpux_clkevt_resume(struct clock_event_device *clkevt) -{ - mtk_cpux_set_irq(to_timer_of(clkevt), true); - return 0; -} - static void mtk_syst_ack_irq(struct timer_of *to) { /* Clear and disable interrupt */ @@ -340,60 +281,6 @@ static struct timer_of to = { }, }; -static int __init mtk_cpux_init(struct device_node *node) -{ - static struct timer_of to_cpux; - u32 freq, val; - int ret; - - /* - * There are per-cpu interrupts for the CPUX General Purpose Timer - * but since this timer feeds the AArch64 System Timer we can rely - * on the CPU timer PPIs as well, so we don't declare TIMER_OF_IRQ. - */ - to_cpux.flags = TIMER_OF_BASE | TIMER_OF_CLOCK; - to_cpux.clkevt.name = "mtk-cpuxgpt"; - to_cpux.clkevt.rating = 10; - to_cpux.clkevt.cpumask = cpu_possible_mask; - to_cpux.clkevt.set_state_shutdown = mtk_cpux_clkevt_shutdown; - to_cpux.clkevt.tick_resume = mtk_cpux_clkevt_resume; - - /* If this fails, bad things are about to happen... */ - ret = timer_of_init(node, &to_cpux); - if (ret) { - WARN(1, "Cannot start CPUX timers.\n"); - return ret; - } - - /* - * Check if we're given a clock with the right frequency for this - * timer, otherwise warn but keep going with the setup anyway, as - * that makes it possible to still boot the kernel, even though - * it may not work correctly (random lockups, etc). - * The reason behind this is that having an early UART may not be - * possible for everyone and this gives a chance to retrieve kmsg - * for eventual debugging even on consumer devices. - */ - freq = timer_of_rate(&to_cpux); - if (freq > 13000000) - WARN(1, "Requested unsupported timer frequency %u\n", freq); - - /* Clock input is 26MHz, set DIV2 to achieve 13MHz clock */ - val = mtk_cpux_readl(CPUX_IDX_GLOBAL_CTRL, &to_cpux); - val &= ~CPUX_CLK_DIV_MASK; - val |= CPUX_CLK_DIV2; - mtk_cpux_writel(val, CPUX_IDX_GLOBAL_CTRL, &to_cpux); - - /* Enable all CPUXGPT timers */ - val = mtk_cpux_readl(CPUX_IDX_GLOBAL_CTRL, &to_cpux); - mtk_cpux_writel(val | CPUX_ENABLE, CPUX_IDX_GLOBAL_CTRL, &to_cpux); - - clockevents_config_and_register(&to_cpux.clkevt, timer_of_rate(&to_cpux), - TIMER_SYNC_TICKS, 0xffffffff); - - return 0; -} - static int __init mtk_syst_init(struct device_node *node) { int ret; @@ -452,4 +339,3 @@ static int __init mtk_gpt_init(struct device_node *node) } TIMER_OF_DECLARE(mtk_mt6577, "mediatek,mt6577-timer", mtk_gpt_init); TIMER_OF_DECLARE(mtk_mt6765, "mediatek,mt6765-timer", mtk_syst_init); -TIMER_OF_DECLARE(mtk_mt6795, "mediatek,mt6795-systimer", mtk_cpux_init); |