diff options
| author | Meng Yi <meng.yi@nxp.com> | 2017-04-20 07:10:12 (GMT) |
|---|---|---|
| committer | Xie Xiaobo <xiaobo.xie@nxp.com> | 2017-07-14 10:29:50 (GMT) |
| commit | 7323e43b12cf145418c1b27b190ec3edfa7984b6 (patch) | |
| tree | 2639746adb6b2cc345ae377cae858d0781149e77 /drivers/soc | |
| parent | bc153d0e78186cfc06d16d228777625277882ea0 (diff) | |
| download | linux-7323e43b12cf145418c1b27b190ec3edfa7984b6.tar.xz | |
Fix errata A-007728 for flextimer
If the FTM counter reaches the FTM_MOD value between the reading of the
TOF bit and the writing of 0 to the TOF bit, the process of clearing the
TOF bit does not work as expected when FTMx_CONF[NUMTOF] != 0 and the
current TOF count is less than FTMx_CONF[NUMTOF]. If the above condition
is met, the TOF bit remains set. If the TOF interrupt is enabled
(FTMx_SC[TOIE] = 1), the TOF interrupt also remains asserted.
Above is the errata discription
In one word: software clearing TOF bit not works when FTMx_CONF[NUMTOF]
was seted as nonzero and FTM counter reaches the FTM_MOD value.
The workaround is clearing TOF bit until it works(FTM counter doesn't
always reache the FTM_MOD anyway),which may cost some cycles.
Signed-off-by: Meng Yi <meng.yi@nxp.com>
Diffstat (limited to 'drivers/soc')
| -rw-r--r-- | drivers/soc/fsl/layerscape/ftm_alarm.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/soc/fsl/layerscape/ftm_alarm.c b/drivers/soc/fsl/layerscape/ftm_alarm.c index f5d6de6..6f9882f 100644 --- a/drivers/soc/fsl/layerscape/ftm_alarm.c +++ b/drivers/soc/fsl/layerscape/ftm_alarm.c @@ -79,11 +79,11 @@ static inline void ftm_counter_disable(void __iomem *base) static inline void ftm_irq_acknowledge(void __iomem *base) { - u32 val; + unsigned int timeout = 100; - val = ftm_readl(base + FTM_SC); - val &= ~FTM_SC_TOF; - ftm_writel(val, base + FTM_SC); + while ((FTM_SC_TOF & ftm_readl(base + FTM_SC)) && timeout--) + ftm_writel(ftm_readl(base + FTM_SC) & (~FTM_SC_TOF), + base + FTM_SC); } static inline void ftm_irq_enable(void __iomem *base) |