From 471ef0b5a8aaca4296108e756b970acfc499ede4 Mon Sep 17 00:00:00 2001 From: Daniel Lezcano Date: Mon, 19 Aug 2024 12:03:35 +0200 Subject: [PATCH 1/3] clocksource/drivers/timer-of: Remove percpu irq related code MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit GCC's named address space checks errors out with: drivers/clocksource/timer-of.c: In function ‘timer_of_irq_exit’: drivers/clocksource/timer-of.c:29:46: error: passing argument 2 of ‘free_percpu_irq’ from pointer to non-enclosed address space 29 | free_percpu_irq(of_irq->irq, clkevt); | ^~~~~~ In file included from drivers/clocksource/timer-of.c:8: ./include/linux/interrupt.h:201:43: note: expected ‘__seg_gs void *’ but argument is of type ‘struct clock_event_device *’ 201 | extern void free_percpu_irq(unsigned int, void __percpu *); | ^~~~~~~~~~~~~~~ drivers/clocksource/timer-of.c: In function ‘timer_of_irq_init’: drivers/clocksource/timer-of.c:74:51: error: passing argument 4 of ‘request_percpu_irq’ from pointer to non-enclosed address space 74 | np->full_name, clkevt) : | ^~~~~~ ./include/linux/interrupt.h:190:56: note: expected ‘__seg_gs void *’ but argument is of type ‘struct clock_event_device *’ 190 | const char *devname, void __percpu *percpu_dev_id) Sparse warns about: timer-of.c:29:46: warning: incorrect type in argument 2 (different address spaces) timer-of.c:29:46: expected void [noderef] __percpu * timer-of.c:29:46: got struct clock_event_device *clkevt timer-of.c:74:51: warning: incorrect type in argument 4 (different address spaces) timer-of.c:74:51: expected void [noderef] __percpu *percpu_dev_id timer-of.c:74:51: got struct clock_event_device *clkevt It appears the code is incorrect as reported by Uros Bizjak: "The referred code is questionable as it tries to reuse the clkevent pointer once as percpu pointer and once as generic pointer, which should be avoided." This change removes the percpu related code as no drivers is using it. [Daniel: Fixed the description] Fixes: dc11bae785295 ("clocksource/drivers: Add timer-of common init routine") Reported-by: Uros Bizjak Tested-by: Uros Bizjak Link: https://lore.kernel.org/r/20240819100335.2394751-1-daniel.lezcano@linaro.org Signed-off-by: Daniel Lezcano --- drivers/clocksource/timer-of.c | 17 ++++------------- drivers/clocksource/timer-of.h | 1 - 2 files changed, 4 insertions(+), 14 deletions(-) diff --git a/drivers/clocksource/timer-of.c b/drivers/clocksource/timer-of.c index c3f54d9912be7..420202bf76e42 100644 --- a/drivers/clocksource/timer-of.c +++ b/drivers/clocksource/timer-of.c @@ -25,10 +25,7 @@ static __init void timer_of_irq_exit(struct of_timer_irq *of_irq) struct clock_event_device *clkevt = &to->clkevt; - if (of_irq->percpu) - free_percpu_irq(of_irq->irq, clkevt); - else - free_irq(of_irq->irq, clkevt); + free_irq(of_irq->irq, clkevt); } /** @@ -42,9 +39,6 @@ static __init void timer_of_irq_exit(struct of_timer_irq *of_irq) * - Get interrupt number by name * - Get interrupt number by index * - * When the interrupt is per CPU, 'request_percpu_irq()' is called, - * otherwise 'request_irq()' is used. - * * Returns 0 on success, < 0 otherwise */ static __init int timer_of_irq_init(struct device_node *np, @@ -69,12 +63,9 @@ static __init int timer_of_irq_init(struct device_node *np, return -EINVAL; } - ret = of_irq->percpu ? - request_percpu_irq(of_irq->irq, of_irq->handler, - np->full_name, clkevt) : - request_irq(of_irq->irq, of_irq->handler, - of_irq->flags ? of_irq->flags : IRQF_TIMER, - np->full_name, clkevt); + ret = request_irq(of_irq->irq, of_irq->handler, + of_irq->flags ? of_irq->flags : IRQF_TIMER, + np->full_name, clkevt); if (ret) { pr_err("Failed to request irq %d for %pOF\n", of_irq->irq, np); return ret; diff --git a/drivers/clocksource/timer-of.h b/drivers/clocksource/timer-of.h index a5478f3e8589d..01a2c6b7db065 100644 --- a/drivers/clocksource/timer-of.h +++ b/drivers/clocksource/timer-of.h @@ -11,7 +11,6 @@ struct of_timer_irq { int irq; int index; - int percpu; const char *name; unsigned long flags; irq_handler_t handler; From 5b8843fcd49827813da80c0f590a17ae4ce93c5d Mon Sep 17 00:00:00 2001 From: Jacky Bai Date: Thu, 25 Jul 2024 15:33:54 -0400 Subject: [PATCH 2/3] clocksource/drivers/imx-tpm: Fix return -ETIME when delta exceeds INT_MAX In tpm_set_next_event(delta), return -ETIME by wrong cast to int when delta is larger than INT_MAX. For example: tpm_set_next_event(delta = 0xffff_fffe) { ... next = tpm_read_counter(); // assume next is 0x10 next += delta; // next will 0xffff_fffe + 0x10 = 0x1_0000_000e now = tpm_read_counter(); // now is 0x10 ... return (int)(next - now) <= 0 ? -ETIME : 0; ^^^^^^^^^^ 0x1_0000_000e - 0x10 = 0xffff_fffe, which is -2 when cast to int. So return -ETIME. } To fix this, introduce a 'prev' variable and check if 'now - prev' is larger than delta. Cc: stable@vger.kernel.org Fixes: 059ab7b82eec ("clocksource/drivers/imx-tpm: Add imx tpm timer support") Signed-off-by: Jacky Bai Reviewed-by: Peng Fan Reviewed-by: Ye Li Reviewed-by: Jason Liu Signed-off-by: Frank Li Link: https://lore.kernel.org/r/20240725193355.1436005-1-Frank.Li@nxp.com Signed-off-by: Daniel Lezcano --- drivers/clocksource/timer-imx-tpm.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/clocksource/timer-imx-tpm.c b/drivers/clocksource/timer-imx-tpm.c index bd64a8a8427f3..cd23caf1e5999 100644 --- a/drivers/clocksource/timer-imx-tpm.c +++ b/drivers/clocksource/timer-imx-tpm.c @@ -83,10 +83,10 @@ static u64 notrace tpm_read_sched_clock(void) static int tpm_set_next_event(unsigned long delta, struct clock_event_device *evt) { - unsigned long next, now; + unsigned long next, prev, now; - next = tpm_read_counter(); - next += delta; + prev = tpm_read_counter(); + next = prev + delta; writel(next, timer_base + TPM_C0V); now = tpm_read_counter(); @@ -96,7 +96,7 @@ static int tpm_set_next_event(unsigned long delta, * of writing CNT registers which may cause the min_delta event got * missed, so we need add a ETIME check here in case it happened. */ - return (int)(next - now) <= 0 ? -ETIME : 0; + return (now - prev) >= delta ? -ETIME : 0; } static int tpm_set_state_oneshot(struct clock_event_device *evt) From 3d5c2f8e75a55cfb11a85086c71996af0354a1fb Mon Sep 17 00:00:00 2001 From: Jacky Bai Date: Thu, 25 Jul 2024 15:33:55 -0400 Subject: [PATCH 3/3] clocksource/drivers/imx-tpm: Fix next event not taking effect sometime The value written into the TPM CnV can only be updated into the hardware when the counter increases. Additional writes to the CnV write buffer are ignored until the register has been updated. Therefore, we need to check if the CnV has been updated before continuing. This may require waiting for 1 counter cycle in the worst case. Cc: stable@vger.kernel.org Fixes: 059ab7b82eec ("clocksource/drivers/imx-tpm: Add imx tpm timer support") Signed-off-by: Jacky Bai Reviewed-by: Peng Fan Reviewed-by: Ye Li Reviewed-by: Jason Liu Signed-off-by: Frank Li Link: https://lore.kernel.org/r/20240725193355.1436005-2-Frank.Li@nxp.com Signed-off-by: Daniel Lezcano --- drivers/clocksource/timer-imx-tpm.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/clocksource/timer-imx-tpm.c b/drivers/clocksource/timer-imx-tpm.c index cd23caf1e5999..92c025b70eb62 100644 --- a/drivers/clocksource/timer-imx-tpm.c +++ b/drivers/clocksource/timer-imx-tpm.c @@ -90,6 +90,14 @@ static int tpm_set_next_event(unsigned long delta, writel(next, timer_base + TPM_C0V); now = tpm_read_counter(); + /* + * Need to wait CNT increase at least 1 cycle to make sure + * the C0V has been updated into HW. + */ + if ((next & 0xffffffff) != readl(timer_base + TPM_C0V)) + while (now == tpm_read_counter()) + ; + /* * NOTE: We observed in a very small probability, the bus fabric * contention between GPU and A7 may results a few cycles delay