| Message ID | 20190211225907.38511-1-tony@atomide.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
| Series | clk: clk-twl6040: Fix imprecise external abort for pdmclk | expand |
On 12/02/2019 0.59, Tony Lindgren wrote: > I noticed that modprobe clk-twl6040 can fail after a cold boot with: > abe_cm:clk:0010:0: failed to enable > ... > Unhandled fault: imprecise external abort (0x1406) at 0xbe896b20 > > WARNING: CPU: 1 PID: 29 at drivers/clk/clk.c:828 clk_core_disable_lock+0x18/0x24 > ... > (clk_core_disable_lock) from [<c0123534>] (_disable_clocks+0x18/0x90) > (_disable_clocks) from [<c0124040>] (_idle+0x17c/0x244) > (_idle) from [<c0125ad4>] (omap_hwmod_idle+0x24/0x44) > (omap_hwmod_idle) from [<c053a038>] (sysc_runtime_suspend+0x48/0x108) > (sysc_runtime_suspend) from [<c06084c4>] (__rpm_callback+0x144/0x1d8) > (__rpm_callback) from [<c0608578>] (rpm_callback+0x20/0x80) > (rpm_callback) from [<c0607034>] (rpm_suspend+0x120/0x694) > (rpm_suspend) from [<c0607a78>] (__pm_runtime_idle+0x60/0x84) > (__pm_runtime_idle) from [<c053aaf0>] (sysc_probe+0x874/0xf2c) > (sysc_probe) from [<c05fecd4>] (platform_drv_probe+0x48/0x98) > > After searching around for a similar issue, I came across an earlier fix > that never got merged upstream in the Android tree for glass-omap-xrr02. > There is patch "MFD: twl6040-codec: Implement PDMCLK cold temp errata" > by Misael Lopez Cruz <misael.lopez@ti.com>. > > Based on my observations, this fix is also needed when cold booting > devices, and not just for deeper idle modes. Since we now have a clock > driver for pdmclk, let's fix the issue in twl6040_pdmclk_prepare(). Thanks for figuring it out! I came across this patch a while ago and not sure why I did not ported it. Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com> > Cc: Misael Lopez Cruz <misael.lopez@ti.com> > Cc: Peter Ujfalusi <peter.ujfalusi@ti.com> > Signed-off-by: Tony Lindgren <tony@atomide.com> > --- > drivers/clk/clk-twl6040.c | 53 +++++++++++++++++++++++++++++++++++++-- > 1 file changed, 51 insertions(+), 2 deletions(-) > > diff --git a/drivers/clk/clk-twl6040.c b/drivers/clk/clk-twl6040.c > --- a/drivers/clk/clk-twl6040.c > +++ b/drivers/clk/clk-twl6040.c > @@ -41,6 +41,43 @@ static int twl6040_pdmclk_is_prepared(struct clk_hw *hw) > return pdmclk->enabled; > } > > +static int twl6040_pdmclk_reset_one_clock(struct twl6040_pdmclk *pdmclk, > + unsigned int reg) > +{ > + const u8 reset_mask = TWL6040_HPLLRST; /* Same for HPPLL and LPPLL */ > + int ret; > + > + ret = twl6040_set_bits(pdmclk->twl6040, reg, reset_mask); > + if (ret < 0) > + return ret; > + > + ret = twl6040_clear_bits(pdmclk->twl6040, reg, reset_mask); > + if (ret < 0) > + return ret; > + > + return 0; > +} > + > +/* > + * TWL6040A2 Phoenix Audio IC erratum #6: "PDM Clock Generation Issue At > + * Cold Temperature". This affects cold boot and deeper idle states it > + * seems. The workaround consists of resetting HPPLL and LPPLL. > + */ > +static int twl6040_pdmclk_quirk_reset_clocks(struct twl6040_pdmclk *pdmclk) > +{ > + int ret; > + > + ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_HPPLLCTL); > + if (ret) > + return ret; > + > + ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_LPPLLCTL); > + if (ret) > + return ret; > + > + return 0; > +} > + > static int twl6040_pdmclk_prepare(struct clk_hw *hw) > { > struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk, > @@ -48,8 +85,20 @@ static int twl6040_pdmclk_prepare(struct clk_hw *hw) > int ret; > > ret = twl6040_power(pdmclk->twl6040, 1); > - if (!ret) > - pdmclk->enabled = 1; > + if (ret) > + return ret; > + > + ret = twl6040_pdmclk_quirk_reset_clocks(pdmclk); > + if (ret) > + goto out_err; > + > + pdmclk->enabled = 1; > + > + return 0; > + > +out_err: > + dev_err(pdmclk->dev, "%s: error %i\n", __func__, ret); > + twl6040_power(pdmclk->twl6040, 0); > > return ret; > } > - Péter Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
Quoting Tony Lindgren (2019-02-11 14:59:07) > I noticed that modprobe clk-twl6040 can fail after a cold boot with: > abe_cm:clk:0010:0: failed to enable > ... > Unhandled fault: imprecise external abort (0x1406) at 0xbe896b20 > > WARNING: CPU: 1 PID: 29 at drivers/clk/clk.c:828 clk_core_disable_lock+0x18/0x24 > ... > (clk_core_disable_lock) from [<c0123534>] (_disable_clocks+0x18/0x90) > (_disable_clocks) from [<c0124040>] (_idle+0x17c/0x244) > (_idle) from [<c0125ad4>] (omap_hwmod_idle+0x24/0x44) > (omap_hwmod_idle) from [<c053a038>] (sysc_runtime_suspend+0x48/0x108) > (sysc_runtime_suspend) from [<c06084c4>] (__rpm_callback+0x144/0x1d8) > (__rpm_callback) from [<c0608578>] (rpm_callback+0x20/0x80) > (rpm_callback) from [<c0607034>] (rpm_suspend+0x120/0x694) > (rpm_suspend) from [<c0607a78>] (__pm_runtime_idle+0x60/0x84) > (__pm_runtime_idle) from [<c053aaf0>] (sysc_probe+0x874/0xf2c) > (sysc_probe) from [<c05fecd4>] (platform_drv_probe+0x48/0x98) > > After searching around for a similar issue, I came across an earlier fix > that never got merged upstream in the Android tree for glass-omap-xrr02. > There is patch "MFD: twl6040-codec: Implement PDMCLK cold temp errata" > by Misael Lopez Cruz <misael.lopez@ti.com>. > > Based on my observations, this fix is also needed when cold booting > devices, and not just for deeper idle modes. Since we now have a clock > driver for pdmclk, let's fix the issue in twl6040_pdmclk_prepare(). > > Cc: Misael Lopez Cruz <misael.lopez@ti.com> > Cc: Peter Ujfalusi <peter.ujfalusi@ti.com> > Signed-off-by: Tony Lindgren <tony@atomide.com> Should this be backported to stable trees?
* Stephen Boyd <sboyd@kernel.org> [190213 17:52]: > Quoting Tony Lindgren (2019-02-11 14:59:07) > > I noticed that modprobe clk-twl6040 can fail after a cold boot with: > > abe_cm:clk:0010:0: failed to enable > > ... > > Unhandled fault: imprecise external abort (0x1406) at 0xbe896b20 > > > > WARNING: CPU: 1 PID: 29 at drivers/clk/clk.c:828 clk_core_disable_lock+0x18/0x24 > > ... > > (clk_core_disable_lock) from [<c0123534>] (_disable_clocks+0x18/0x90) > > (_disable_clocks) from [<c0124040>] (_idle+0x17c/0x244) > > (_idle) from [<c0125ad4>] (omap_hwmod_idle+0x24/0x44) > > (omap_hwmod_idle) from [<c053a038>] (sysc_runtime_suspend+0x48/0x108) > > (sysc_runtime_suspend) from [<c06084c4>] (__rpm_callback+0x144/0x1d8) > > (__rpm_callback) from [<c0608578>] (rpm_callback+0x20/0x80) > > (rpm_callback) from [<c0607034>] (rpm_suspend+0x120/0x694) > > (rpm_suspend) from [<c0607a78>] (__pm_runtime_idle+0x60/0x84) > > (__pm_runtime_idle) from [<c053aaf0>] (sysc_probe+0x874/0xf2c) > > (sysc_probe) from [<c05fecd4>] (platform_drv_probe+0x48/0x98) > > > > After searching around for a similar issue, I came across an earlier fix > > that never got merged upstream in the Android tree for glass-omap-xrr02. > > There is patch "MFD: twl6040-codec: Implement PDMCLK cold temp errata" > > by Misael Lopez Cruz <misael.lopez@ti.com>. > > > > Based on my observations, this fix is also needed when cold booting > > devices, and not just for deeper idle modes. Since we now have a clock > > driver for pdmclk, let's fix the issue in twl6040_pdmclk_prepare(). > > > > Cc: Misael Lopez Cruz <misael.lopez@ti.com> > > Cc: Peter Ujfalusi <peter.ujfalusi@ti.com> > > Signed-off-by: Tony Lindgren <tony@atomide.com> > > Should this be backported to stable trees? Yes please, I think that's a good idea. Regards, Tony
Quoting Tony Lindgren (2019-02-11 14:59:07) > I noticed that modprobe clk-twl6040 can fail after a cold boot with: > abe_cm:clk:0010:0: failed to enable > ... > Unhandled fault: imprecise external abort (0x1406) at 0xbe896b20 > > WARNING: CPU: 1 PID: 29 at drivers/clk/clk.c:828 clk_core_disable_lock+0x18/0x24 > ... > (clk_core_disable_lock) from [<c0123534>] (_disable_clocks+0x18/0x90) > (_disable_clocks) from [<c0124040>] (_idle+0x17c/0x244) > (_idle) from [<c0125ad4>] (omap_hwmod_idle+0x24/0x44) > (omap_hwmod_idle) from [<c053a038>] (sysc_runtime_suspend+0x48/0x108) > (sysc_runtime_suspend) from [<c06084c4>] (__rpm_callback+0x144/0x1d8) > (__rpm_callback) from [<c0608578>] (rpm_callback+0x20/0x80) > (rpm_callback) from [<c0607034>] (rpm_suspend+0x120/0x694) > (rpm_suspend) from [<c0607a78>] (__pm_runtime_idle+0x60/0x84) > (__pm_runtime_idle) from [<c053aaf0>] (sysc_probe+0x874/0xf2c) > (sysc_probe) from [<c05fecd4>] (platform_drv_probe+0x48/0x98) > > After searching around for a similar issue, I came across an earlier fix > that never got merged upstream in the Android tree for glass-omap-xrr02. > There is patch "MFD: twl6040-codec: Implement PDMCLK cold temp errata" > by Misael Lopez Cruz <misael.lopez@ti.com>. > > Based on my observations, this fix is also needed when cold booting > devices, and not just for deeper idle modes. Since we now have a clock > driver for pdmclk, let's fix the issue in twl6040_pdmclk_prepare(). > > Cc: Misael Lopez Cruz <misael.lopez@ti.com> > Cc: Peter Ujfalusi <peter.ujfalusi@ti.com> > Signed-off-by: Tony Lindgren <tony@atomide.com> > --- Applied to clk-next + added a stable tag
diff --git a/drivers/clk/clk-twl6040.c b/drivers/clk/clk-twl6040.c --- a/drivers/clk/clk-twl6040.c +++ b/drivers/clk/clk-twl6040.c @@ -41,6 +41,43 @@ static int twl6040_pdmclk_is_prepared(struct clk_hw *hw) return pdmclk->enabled; } +static int twl6040_pdmclk_reset_one_clock(struct twl6040_pdmclk *pdmclk, + unsigned int reg) +{ + const u8 reset_mask = TWL6040_HPLLRST; /* Same for HPPLL and LPPLL */ + int ret; + + ret = twl6040_set_bits(pdmclk->twl6040, reg, reset_mask); + if (ret < 0) + return ret; + + ret = twl6040_clear_bits(pdmclk->twl6040, reg, reset_mask); + if (ret < 0) + return ret; + + return 0; +} + +/* + * TWL6040A2 Phoenix Audio IC erratum #6: "PDM Clock Generation Issue At + * Cold Temperature". This affects cold boot and deeper idle states it + * seems. The workaround consists of resetting HPPLL and LPPLL. + */ +static int twl6040_pdmclk_quirk_reset_clocks(struct twl6040_pdmclk *pdmclk) +{ + int ret; + + ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_HPPLLCTL); + if (ret) + return ret; + + ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_LPPLLCTL); + if (ret) + return ret; + + return 0; +} + static int twl6040_pdmclk_prepare(struct clk_hw *hw) { struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk, @@ -48,8 +85,20 @@ static int twl6040_pdmclk_prepare(struct clk_hw *hw) int ret; ret = twl6040_power(pdmclk->twl6040, 1); - if (!ret) - pdmclk->enabled = 1; + if (ret) + return ret; + + ret = twl6040_pdmclk_quirk_reset_clocks(pdmclk); + if (ret) + goto out_err; + + pdmclk->enabled = 1; + + return 0; + +out_err: + dev_err(pdmclk->dev, "%s: error %i\n", __func__, ret); + twl6040_power(pdmclk->twl6040, 0); return ret; }
I noticed that modprobe clk-twl6040 can fail after a cold boot with: abe_cm:clk:0010:0: failed to enable ... Unhandled fault: imprecise external abort (0x1406) at 0xbe896b20 WARNING: CPU: 1 PID: 29 at drivers/clk/clk.c:828 clk_core_disable_lock+0x18/0x24 ... (clk_core_disable_lock) from [<c0123534>] (_disable_clocks+0x18/0x90) (_disable_clocks) from [<c0124040>] (_idle+0x17c/0x244) (_idle) from [<c0125ad4>] (omap_hwmod_idle+0x24/0x44) (omap_hwmod_idle) from [<c053a038>] (sysc_runtime_suspend+0x48/0x108) (sysc_runtime_suspend) from [<c06084c4>] (__rpm_callback+0x144/0x1d8) (__rpm_callback) from [<c0608578>] (rpm_callback+0x20/0x80) (rpm_callback) from [<c0607034>] (rpm_suspend+0x120/0x694) (rpm_suspend) from [<c0607a78>] (__pm_runtime_idle+0x60/0x84) (__pm_runtime_idle) from [<c053aaf0>] (sysc_probe+0x874/0xf2c) (sysc_probe) from [<c05fecd4>] (platform_drv_probe+0x48/0x98) After searching around for a similar issue, I came across an earlier fix that never got merged upstream in the Android tree for glass-omap-xrr02. There is patch "MFD: twl6040-codec: Implement PDMCLK cold temp errata" by Misael Lopez Cruz <misael.lopez@ti.com>. Based on my observations, this fix is also needed when cold booting devices, and not just for deeper idle modes. Since we now have a clock driver for pdmclk, let's fix the issue in twl6040_pdmclk_prepare(). Cc: Misael Lopez Cruz <misael.lopez@ti.com> Cc: Peter Ujfalusi <peter.ujfalusi@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> --- drivers/clk/clk-twl6040.c | 53 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 51 insertions(+), 2 deletions(-)