From b91cf01cf3e63a627b3b65f4284dcf9a4deb80f9 Mon Sep 17 00:00:00 2001 From: Inochi Amaoto Date: Mon, 4 Dec 2023 17:51:08 +0800 Subject: [PATCH 1/7] dt-bindings: timer: thead,c900-aclint-mtimer: separate mtime and mtimecmp regs The timer registers of aclint don't follow the clint layout and can be mapped on any different offset. As sg2042 uses separated timer and mswi for its clint, it should follow the aclint spec and have separated registers. The previous patch introduced a new type of T-HEAD aclint timer which has clint timer layout. Although it has the clint timer layout, it should follow the aclint spec and uses the separated mtime and mtimecmp regs. So a ABI change is needed to make the timer fit the aclint spec. To make T-HEAD aclint timer more closer to the aclint spec, use regs-names to represent the mtimecmp register, which can avoid hack for unsupport mtime register of T-HEAD aclint timer. Also, as T-HEAD aclint only supports mtimecmp, it is unnecessary to implement the whole aclint spec. To make this binding T-HEAD specific, only add reg-name for existed register. For details, see the discussion in the last link. Signed-off-by: Inochi Amaoto Fixes: 4734449f7311 ("dt-bindings: timer: Add Sophgo sg2042 CLINT timer") Link: https://lists.infradead.org/pipermail/opensbi/2023-October/005693.html Link: https://github.com/riscv/riscv-aclint/blob/main/riscv-aclint.adoc Link: https://lore.kernel.org/all/IA1PR20MB4953F9D77FFC76A9D236922DBBB6A@IA1PR20MB4953.namprd20.prod.outlook.com/ Acked-by: Guo Ren Acked-by: Conor Dooley Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/IA1PR20MB49531ED1BCC00D6B265C2D10BB86A@IA1PR20MB4953.namprd20.prod.outlook.com --- .../bindings/timer/thead,c900-aclint-mtimer.yaml | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml b/Documentation/devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml index fbd235650e52..2e92bcdeb423 100644 --- a/Documentation/devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml +++ b/Documentation/devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml @@ -17,7 +17,12 @@ properties: - const: thead,c900-aclint-mtimer reg: - maxItems: 1 + items: + - description: MTIMECMP Registers + + reg-names: + items: + - const: mtimecmp interrupts-extended: minItems: 1 @@ -28,6 +33,7 @@ additionalProperties: false required: - compatible - reg + - reg-names - interrupts-extended examples: @@ -39,5 +45,6 @@ examples: <&cpu3intc 7>, <&cpu4intc 7>; reg = <0xac000000 0x00010000>; + reg-names = "mtimecmp"; }; ... From e0cf60151e6317c654c42ba0e8b1fb6ff477489a Mon Sep 17 00:00:00 2001 From: Sia Jee Heng Date: Fri, 1 Dec 2023 20:14:07 +0800 Subject: [PATCH 2/7] dt-bindings: timer: Add StarFive JH8100 clint Add compatible string for the StarFive JH8100 clint. Signed-off-by: Sia Jee Heng Reviewed-by: Ley Foon Tan Acked-by: Conor Dooley Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20231201121410.95298-4-jeeheng.sia@starfivetech.com --- Documentation/devicetree/bindings/timer/sifive,clint.yaml | 1 + 1 file changed, 1 insertion(+) diff --git a/Documentation/devicetree/bindings/timer/sifive,clint.yaml b/Documentation/devicetree/bindings/timer/sifive,clint.yaml index e8be6c470364..01254261e156 100644 --- a/Documentation/devicetree/bindings/timer/sifive,clint.yaml +++ b/Documentation/devicetree/bindings/timer/sifive,clint.yaml @@ -33,6 +33,7 @@ properties: - sifive,fu540-c000-clint # SiFive FU540 - starfive,jh7100-clint # StarFive JH7100 - starfive,jh7110-clint # StarFive JH7110 + - starfive,jh8100-clint # StarFive JH8100 - const: sifive,clint0 # SiFive CLINT v0 IP block - items: - enum: From 6a902b118e7f30dbf0e6248f7b0f97e12c0939c3 Mon Sep 17 00:00:00 2001 From: Joshua Yeong Date: Thu, 16 Nov 2023 18:53:12 +0800 Subject: [PATCH 3/7] clocksource/timer-riscv: Add riscv_clock_shutdown callback Add clocksource detach/shutdown callback to disable RISC-V timer interrupt when switching out riscv timer as clock source Signed-off-by: Joshua Yeong Reviewed-by: Anup Patel Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20231116105312.4800-1-joshua.yeong@starfivetech.com --- drivers/clocksource/timer-riscv.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c index 57857c0dfba9..e66dcbd66566 100644 --- a/drivers/clocksource/timer-riscv.c +++ b/drivers/clocksource/timer-riscv.c @@ -61,12 +61,19 @@ static int riscv_clock_next_event(unsigned long delta, return 0; } +static int riscv_clock_shutdown(struct clock_event_device *evt) +{ + riscv_clock_event_stop(); + return 0; +} + static unsigned int riscv_clock_event_irq; static DEFINE_PER_CPU(struct clock_event_device, riscv_clock_event) = { .name = "riscv_timer_clockevent", .features = CLOCK_EVT_FEAT_ONESHOT, .rating = 100, .set_next_event = riscv_clock_next_event, + .set_state_shutdown = riscv_clock_shutdown, }; /* From b99a212a7697c542b460adaa15d4a98abf8223f0 Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Tue, 14 Nov 2023 09:29:30 +0200 Subject: [PATCH 4/7] clocksource/drivers/timer-ti-dm: Fix make W=n kerneldoc warnings Kernel test robot reports of kerneldoc related warnings that happen with make W=n for "parameter or member not described". These were caused by changes to function parameter names with earlier commits where the kerneldoc parts were not updated. Fixes: 49cd16bb573e ("clocksource/drivers/timer-ti-dm: Simplify register writes with dmtimer_write()") Fixes: a6e543f61531 ("clocksource/drivers/timer-ti-dm: Move struct omap_dm_timer fields to driver") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202311040403.DzIiBuwU-lkp@intel.com/ Closes: https://lore.kernel.org/oe-kbuild-all/202311040606.XL5OcR9O-lkp@intel.com/ Signed-off-by: Tony Lindgren Reviewed-by: Randy Dunlap Tested-by: Randy Dunlap Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20231114072930.40615-1-tony@atomide.com --- drivers/clocksource/timer-ti-dm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/clocksource/timer-ti-dm.c b/drivers/clocksource/timer-ti-dm.c index 5f60f6bd3386..56acf2617262 100644 --- a/drivers/clocksource/timer-ti-dm.c +++ b/drivers/clocksource/timer-ti-dm.c @@ -183,7 +183,7 @@ static inline u32 dmtimer_read(struct dmtimer *timer, u32 reg) * dmtimer_write - write timer registers in posted and non-posted mode * @timer: timer pointer over which write operation is to perform * @reg: lowest byte holds the register offset - * @value: data to write into the register + * @val: data to write into the register * * The posted mode bit is encoded in reg. Note that in posted mode, the write * pending bit must be checked. Otherwise a write on a register which has a @@ -949,7 +949,7 @@ static int omap_dm_timer_set_int_enable(struct omap_dm_timer *cookie, /** * omap_dm_timer_set_int_disable - disable timer interrupts - * @timer: pointer to timer handle + * @cookie: pointer to timer cookie * @mask: bit mask of interrupts to be disabled * * Disables the specified timer interrupts for a timer. From 0515c73467fd550249ef83062e1d03d99c718b4f Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Tue, 5 Dec 2023 15:04:48 -0800 Subject: [PATCH 5/7] clocksource/drivers/cadence-ttc: Fix some kernel-doc warnings Fix some function kernel-doc warnings to placate scripts/kernel-doc. timer-cadence-ttc.c:79: warning: Function parameter or member 'clk_rate_change_nb' not described in 'ttc_timer' timer-cadence-ttc.c:158: warning: Function parameter or member 'cs' not described in '__ttc_clocksource_read' timer-cadence-ttc.c:194: warning: expecting prototype for ttc_set_{shutdown|oneshot|periodic}(). Prototype was for ttc_shutdown() instead timer-cadence-ttc.c:196: warning: No description found for return value of 'ttc_shutdown' timer-cadence-ttc.c:212: warning: No description found for return value of 'ttc_set_periodic' Signed-off-by: Randy Dunlap Cc: Michal Simek Cc: Daniel Lezcano Cc: Thomas Gleixner Cc: linux-arm-kernel@lists.infradead.org Acked-by: Michal Simek Tested-by: Michal Simek Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20231205230448.772-1-rdunlap@infradead.org --- drivers/clocksource/timer-cadence-ttc.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/drivers/clocksource/timer-cadence-ttc.c b/drivers/clocksource/timer-cadence-ttc.c index 32daaac9b132..ca7a06489c40 100644 --- a/drivers/clocksource/timer-cadence-ttc.c +++ b/drivers/clocksource/timer-cadence-ttc.c @@ -69,7 +69,7 @@ * @base_addr: Base address of timer * @freq: Timer input clock frequency * @clk: Associated clock source - * @clk_rate_change_nb Notifier block for clock rate changes + * @clk_rate_change_nb: Notifier block for clock rate changes */ struct ttc_timer { void __iomem *base_addr; @@ -134,7 +134,7 @@ static void ttc_set_interval(struct ttc_timer *timer, * @irq: IRQ number of the Timer * @dev_id: void pointer to the ttc_timer instance * - * returns: Always IRQ_HANDLED - success + * Returns: Always IRQ_HANDLED - success **/ static irqreturn_t ttc_clock_event_interrupt(int irq, void *dev_id) { @@ -151,8 +151,9 @@ static irqreturn_t ttc_clock_event_interrupt(int irq, void *dev_id) /** * __ttc_clocksource_read - Reads the timer counter register + * @cs: &clocksource to read from * - * returns: Current timer counter register value + * Returns: Current timer counter register value **/ static u64 __ttc_clocksource_read(struct clocksource *cs) { @@ -173,7 +174,7 @@ static u64 notrace ttc_sched_clock_read(void) * @cycles: Timer interval ticks * @evt: Address of clock event instance * - * returns: Always 0 - success + * Returns: Always %0 - success **/ static int ttc_set_next_event(unsigned long cycles, struct clock_event_device *evt) @@ -186,9 +187,12 @@ static int ttc_set_next_event(unsigned long cycles, } /** - * ttc_set_{shutdown|oneshot|periodic} - Sets the state of timer - * + * ttc_shutdown - Sets the state of timer * @evt: Address of clock event instance + * + * Used for shutdown or oneshot. + * + * Returns: Always %0 - success **/ static int ttc_shutdown(struct clock_event_device *evt) { @@ -202,6 +206,12 @@ static int ttc_shutdown(struct clock_event_device *evt) return 0; } +/** + * ttc_set_periodic - Sets the state of timer + * @evt: Address of clock event instance + * + * Returns: Always %0 - success + */ static int ttc_set_periodic(struct clock_event_device *evt) { struct ttc_timer_clockevent *ttce = to_ttc_timer_clkevent(evt); From c0c4579d79d0df841e825c68df450909a0032faf Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 12 Dec 2023 22:46:07 +0100 Subject: [PATCH 6/7] clocksource/drivers/ep93xx: Fix error handling during probe When the interrupt property fails to be parsed, ep93xx_timer_of_init() return code ends up uninitialized: drivers/clocksource/timer-ep93xx.c:160:6: error: variable 'ret' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized] if (irq < 0) { ^~~~~~~ drivers/clocksource/timer-ep93xx.c:188:9: note: uninitialized use occurs here return ret; ^~~ drivers/clocksource/timer-ep93xx.c:160:2: note: remove the 'if' if its condition is always false if (irq < 0) { ^~~~~~~~~~~~~~ Simplify this portion to use the normal construct of just checking whether a valid interrupt was returned. Note that irq_of_parse_and_map() never returns a negative value and no other callers check for that either. Fixes: c28ca80ba3b5 ("clocksource: ep93xx: Add driver for Cirrus Logic EP93xx") Signed-off-by: Arnd Bergmann Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20231212214616.193098-1-arnd@kernel.org --- drivers/clocksource/timer-ep93xx.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/clocksource/timer-ep93xx.c b/drivers/clocksource/timer-ep93xx.c index bc0ca6e12334..6981ff3ac8a9 100644 --- a/drivers/clocksource/timer-ep93xx.c +++ b/drivers/clocksource/timer-ep93xx.c @@ -155,9 +155,8 @@ static int __init ep93xx_timer_of_init(struct device_node *np) ep93xx_tcu = tcu; irq = irq_of_parse_and_map(np, 0); - if (irq == 0) - irq = -EINVAL; - if (irq < 0) { + if (!irq) { + ret = -EINVAL; pr_err("EP93XX Timer Can't parse IRQ %d", irq); goto out_free; } From 71fee48fb772ac4f6cfa63dbebc5629de8b4cc09 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 15 Jan 2024 17:35:55 +0100 Subject: [PATCH 7/7] tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplug When offlining and onlining CPUs the overall reported idle and iowait times as reported by /proc/stat jump backward and forward: cpu 132 0 176 225249 47 6 6 21 0 0 cpu0 80 0 115 112575 33 3 4 18 0 0 cpu1 52 0 60 112673 13 3 1 2 0 0 cpu 133 0 177 226681 47 6 6 21 0 0 cpu0 80 0 116 113387 33 3 4 18 0 0 cpu 133 0 178 114431 33 6 6 21 0 0 <---- jump backward cpu0 80 0 116 114247 33 3 4 18 0 0 cpu1 52 0 61 183 0 3 1 2 0 0 <---- idle + iowait start with 0 cpu 133 0 178 228956 47 6 6 21 0 0 <---- jump forward cpu0 81 0 117 114929 33 3 4 18 0 0 Reason for this is that get_idle_time() in fs/proc/stat.c has different sources for both values depending on if a CPU is online or offline: - if a CPU is online the values may be taken from its per cpu tick_cpu_sched structure - if a CPU is offline the values are taken from its per cpu cpustat structure The problem is that the per cpu tick_cpu_sched structure is set to zero on CPU offline. See tick_cancel_sched_timer() in kernel/time/tick-sched.c. Therefore when a CPU is brought offline and online afterwards both its idle and iowait sleeptime will be zero, causing a jump backward in total system idle and iowait sleeptime. In a similar way if a CPU is then brought offline again the total idle and iowait sleeptimes will jump forward. It looks like this behavior was introduced with commit 4b0c0f294f60 ("tick: Cleanup NOHZ per cpu data on cpu down"). This was only noticed now on s390, since we switched to generic idle time reporting with commit be76ea614460 ("s390/idle: remove arch_cpu_idle_time() and corresponding code"). Fix this by preserving the values of idle_sleeptime and iowait_sleeptime members of the per-cpu tick_sched structure on CPU hotplug. Fixes: 4b0c0f294f60 ("tick: Cleanup NOHZ per cpu data on cpu down") Reported-by: Gerald Schaefer Signed-off-by: Heiko Carstens Signed-off-by: Thomas Gleixner Reviewed-by: Frederic Weisbecker Link: https://lore.kernel.org/r/20240115163555.1004144-1-hca@linux.ibm.com --- kernel/time/tick-sched.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index a17d26002831..d2501673028d 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -1576,13 +1576,18 @@ void tick_setup_sched_timer(void) void tick_cancel_sched_timer(int cpu) { struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); + ktime_t idle_sleeptime, iowait_sleeptime; # ifdef CONFIG_HIGH_RES_TIMERS if (ts->sched_timer.base) hrtimer_cancel(&ts->sched_timer); # endif + idle_sleeptime = ts->idle_sleeptime; + iowait_sleeptime = ts->iowait_sleeptime; memset(ts, 0, sizeof(*ts)); + ts->idle_sleeptime = idle_sleeptime; + ts->iowait_sleeptime = iowait_sleeptime; } #endif