On 04/21/2014 11:36 AM, Joel Fernandes wrote: > On 04/21/2014 10:57 AM, Joachim Eastwood wrote: >> On 21 April 2014 17:40, Joel Fernandes <joelf@xxxxxx> wrote: >>> On 04/19/2014 05:25 PM, Joachim Eastwood wrote: >>>> Hello, >>>> >>>> Playing around with an old OMAP pwm driver from NeilBrown. I get the >>>> following warning: >>>> [ 0.979522] omap-pwm omap-pwm.14: omap_dm_timer_set_load >>>> [ 0.979553] ------------[ cut here ]------------ >>>> [ 0.979583] WARNING: CPU: 0 PID: 0 at drivers/bus/omap_l3_noc.c:113 >>>> l3_interrupt_handler+0xf4/0x154() >>>> [ 0.979583] L3 custom error: MASTER:MPU TARGET:L4 PER2 >>>> [ 0.979614] Modules linked in: >>>> [ 0.979614] CPU: 0 PID: 0 Comm: swapper/0 Not tainted >>>> 3.15.0-rc1-00370-gd9d79f4b7b7d-dirty #65 >>>> [ 0.979644] [<c0014f48>] (unwind_backtrace) from [<c0011c2c>] >>>> (show_stack+0x10/0x14) >>>> [ 0.979675] [<c0011c2c>] (show_stack) from [<c05ad3bc>] (dump_stack+0x84/0x94) >>>> [ 0.979705] [<c05ad3bc>] (dump_stack) from [<c0036ba8>] >>>> (warn_slowpath_common+0x70/0x8c) >>>> [ 0.979705] omap-pwm omap-pwm.14: omap_dm_timer_set_match >>>> [ 0.979736] [<c0036ba8>] (warn_slowpath_common) from [<c0036bf4>] >>>> (warn_slowpath_fmt+0x30/0x40) >>>> [ 0.979736] [<c0036bf4>] (warn_slowpath_fmt) from [<c0286c90>] >>>> (l3_interrupt_handler+0xf4/0x154) >>>> [ 0.979766] [<c0286c90>] (l3_interrupt_handler) from [<c0085d1c>] >>>> (handle_irq_event_percpu+0x54/0x1cc) >>>> [ 0.979766] [<c0085d1c>] (handle_irq_event_percpu) from [<c0085ed0>] >>>> (handle_irq_event+0x3c/0x5c) >>>> [ 0.979797] [<c0085ed0>] (handle_irq_event) from [<c0088ed0>] >>>> (handle_fasteoi_irq+0xac/0x1a0) >>>> [ 0.979797] [<c0088ed0>] (handle_fasteoi_irq) from [<c00853fc>] >>>> (generic_handle_irq+0x2c/0x3c) >>>> [ 0.979827] [<c00853fc>] (generic_handle_irq) from [<c000eb20>] >>>> (handle_IRQ+0x40/0x90) >>>> [ 0.979827] [<c000eb20>] (handle_IRQ) from [<c0008594>] >>>> (gic_handle_irq+0x2c/0x5c) >>>> [ 0.979858] [<c0008594>] (gic_handle_irq) from [<c05b4a44>] >>>> (__irq_svc+0x44/0x58) >>>> [ 0.979858] Exception stack(0xc0889f58 to 0xc0889fa0) >>>> [ 0.979858] 9f40: 00000001 00000001 >>>> [ 0.979888] 9f60: 00000000 c0893678 c0888000 c0888000 c08e75a4 >>>> c0890548 c0888000 ee7ffc00 >>>> [ 0.979888] omap-pwm omap-pwm.14: load value: 0xfffd11fe (-192002), >>>> match value: 0xfffffffe (-2) >>>> [ 0.979888] 9f80: c08904e0 c05bdcec 00000000 c0889fa0 c007a190 >>>> c000ee48 20000113 ffffffff >>>> [ 0.979919] [<c05b4a44>] (__irq_svc) from [<c000ee48>] (arch_cpu_idle+0x24/0x30) >>>> [ 0.979919] [<c000ee48>] (arch_cpu_idle) from [<c0071950>] >>>> (cpu_startup_entry+0x138/0x204) >>>> [ 0.979949] [<c0071950>] (cpu_startup_entry) from [<c0822b10>] >>>> (start_kernel+0x370/0x37c) >>>> [ 0.979980] [<c0822b10>] (start_kernel) from [<80008074>] (0x80008074) >>>> [ 0.979980] omap-pwm omap-pwm.14: omap_dm_timer_set_pwm >>>> [ 0.980010] omap-pwm omap-pwm.14: omap_pwm_enable >>>> [ 0.980010] omap-pwm omap-pwm.14: omap_dm_timer_start >>>> [ 0.980010] omap-pwm omap-pwm.14: omap_dm_timer_write_counter >>>> [ 0.980041] ---[ end trace 5d002a14ec98c2ad ]--- >>>> >>>> This seems to be caused by the call into omap_dm_timer_set_load. >>>> >>> >>> Are you talking about this? >>> https://lkml.org/lkml/2012/12/12/51 >>> >>> It doesn't seem to be in mainline though. >> >> No, it isn't. I am trying to revive it and get it upstream. >> >>> I'll add a check for the enable/disable, thanks. >> >> Note that the warning I got might be cause by the pwm-omap and it's >> use of dmtimer api. I will investigate further. >> >> But either way add a check to enable/disable is a good idea. >> > > Sure, I added the check. The patch depends on a few other pending > patches so I just zipped all together. It would be great if you could > apply them and confirm it fixes the problem, then I can add your > tested-by and include it in the next series. Lost track that the mailing list was CC'd so included the latest patch (check for pm_runtime_get_sync) inline below. Dependent patches are at [1]. Regards, -Joel [1] https://lkml.org/lkml/2014/4/16/737 ---8<---------- >From b5884b869a21ffe5472edc59bd07d58b104284b9 Mon Sep 17 00:00:00 2001 From: Joel Fernandes <joelf@xxxxxx> Date: Mon, 21 Apr 2014 11:05:10 -0500 Subject: [PATCH 10/10] ARM: OMAP: dmtimer: Check return of pm_runtime_get_sync omap_timer_enable doesn't check return value, this can lead to nasty bus errors. Add a check and report issues. Signed-off-by: Joel Fernandes <joelf@xxxxxx> --- arch/arm/plat-omap/dmtimer.c | 61 +++++++++++++++++++++++------ arch/arm/plat-omap/include/plat/dmtimer.h | 2 +- 2 files changed, 50 insertions(+), 13 deletions(-) diff --git a/arch/arm/plat-omap/dmtimer.c b/arch/arm/plat-omap/dmtimer.c index 1fd30fa..9403d450 100644 --- a/arch/arm/plat-omap/dmtimer.c +++ b/arch/arm/plat-omap/dmtimer.c @@ -164,7 +164,9 @@ static int omap_dm_timer_prepare(struct omap_dm_timer *timer) } } - omap_dm_timer_enable(timer); + rc = omap_dm_timer_enable(timer); + if(rc) + return rc; if (timer->capability & OMAP_TIMER_NEEDS_RESET) { rc = omap_dm_timer_reset(timer); @@ -375,11 +377,15 @@ int omap_dm_timer_free(struct omap_dm_timer *timer) } EXPORT_SYMBOL_GPL(omap_dm_timer_free); -void omap_dm_timer_enable(struct omap_dm_timer *timer) +int omap_dm_timer_enable(struct omap_dm_timer *timer) { - int c; + int c, err; - pm_runtime_get_sync(&timer->pdev->dev); + err = pm_runtime_get_sync(&timer->pdev->dev); + if (err < 0) { + pr_err("%s: timer could not be get_synced.\n", __func__); + return err; + } if (!(timer->capability & OMAP_TIMER_ALWON)) { if (timer->get_context_loss_count) { @@ -392,6 +398,7 @@ void omap_dm_timer_enable(struct omap_dm_timer *timer) omap_timer_restore_context(timer); } } + return 0; } EXPORT_SYMBOL_GPL(omap_dm_timer_enable); @@ -432,11 +439,14 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_trigger); int omap_dm_timer_start(struct omap_dm_timer *timer) { u32 l; + int rc; if (unlikely(!timer)) return -EINVAL; - omap_dm_timer_enable(timer); + rc = omap_dm_timer_enable(timer); + if (rc) + return rc; l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG); if (!(l & OMAP_TIMER_CTRL_ST)) { @@ -534,11 +544,15 @@ int omap_dm_timer_set_load(struct omap_dm_timer *timer, int autoreload, unsigned int load) { u32 mask = ~0, val = 0; + int rc; if (unlikely(!timer)) return -EINVAL; - omap_dm_timer_enable(timer); + rc = omap_dm_timer_enable(timer); + if (rc) + return rc; + if (autoreload) val |= OMAP_TIMER_CTRL_AR; else @@ -560,11 +574,14 @@ int omap_dm_timer_set_load_start(struct omap_dm_timer *timer, int autoreload, unsigned int load) { u32 l; + int rc; if (unlikely(!timer)) return -EINVAL; - omap_dm_timer_enable(timer); + rc = omap_dm_timer_enable(timer); + if (rc) + return rc; l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG); if (autoreload) { @@ -588,11 +605,15 @@ int omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable, unsigned int match) { u32 mask = ~0, val = 0; + int rc; if (unlikely(!timer)) return -EINVAL; - omap_dm_timer_enable(timer); + rc = omap_dm_timer_enable(timer); + if (rc) + return rc; + if (enable) val |= OMAP_TIMER_CTRL_CE; else @@ -613,11 +634,15 @@ int omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on, int toggle, int trigger) { u32 mask = ~0, val = 0; + int rc; if (unlikely(!timer)) return -EINVAL; - omap_dm_timer_enable(timer); + rc = omap_dm_timer_enable(timer); + if (rc) + return rc; + mask &= ~(OMAP_TIMER_CTRL_GPOCFG | OMAP_TIMER_CTRL_SCPWM | OMAP_TIMER_CTRL_PT | (0x03 << 10)); if (def_on) @@ -637,11 +662,15 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_set_pwm); int omap_dm_timer_set_prescaler(struct omap_dm_timer *timer, int prescaler) { u32 mask = ~0, val = 0; + int rc; if (unlikely(!timer)) return -EINVAL; - omap_dm_timer_enable(timer); + rc = omap_dm_timer_enable(timer); + if (rc) + return rc; + mask &= ~(OMAP_TIMER_CTRL_PRE | (0x07 << 2)); if (prescaler >= 0x00 && prescaler <= 0x07) { val |= OMAP_TIMER_CTRL_PRE; @@ -659,10 +688,15 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_set_prescaler); int omap_dm_timer_set_int_enable(struct omap_dm_timer *timer, unsigned int value) { + int rc; + if (unlikely(!timer)) return -EINVAL; - omap_dm_timer_enable(timer); + rc = omap_dm_timer_enable(timer); + if (rc) + return rc; + __omap_dm_timer_int_enable(timer, value); /* Save the context */ @@ -683,11 +717,14 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_set_int_enable); int omap_dm_timer_set_int_disable(struct omap_dm_timer *timer, u32 mask) { u32 l = mask; + int rc; if (unlikely(!timer)) return -EINVAL; - omap_dm_timer_enable(timer); + rc = omap_dm_timer_enable(timer); + if (rc) + return rc; if (timer->revision == 1) l = __raw_readl(timer->irq_ena) & ~mask; diff --git a/arch/arm/plat-omap/include/plat/dmtimer.h b/arch/arm/plat-omap/include/plat/dmtimer.h index fe3780a..6b6fbd2 100644 --- a/arch/arm/plat-omap/include/plat/dmtimer.h +++ b/arch/arm/plat-omap/include/plat/dmtimer.h @@ -130,7 +130,7 @@ struct omap_dm_timer *omap_dm_timer_request_specific(int timer_id); struct omap_dm_timer *omap_dm_timer_request_by_cap(u32 cap); struct omap_dm_timer *omap_dm_timer_request_by_node(struct device_node *np); int omap_dm_timer_free(struct omap_dm_timer *timer); -void omap_dm_timer_enable(struct omap_dm_timer *timer); +int omap_dm_timer_enable(struct omap_dm_timer *timer); void omap_dm_timer_disable(struct omap_dm_timer *timer); int omap_dm_timer_get_irq(struct omap_dm_timer *timer); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
