Commit Graph

12 Commits

Author SHA1 Message Date
Jacky Bai
3ded318cf0 clocksource/drivers/imx-tpm: Fix next event not taking effect sometime
commit 3d5c2f8e75a55cfb11a85086c71996af0354a1fb upstream.

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: 059ab7b82e ("clocksource/drivers/imx-tpm: Add imx tpm timer support")
Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Ye Li <ye.li@nxp.com>
Reviewed-by: Jason Liu <jason.hui.liu@nxp.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20240725193355.1436005-2-Frank.Li@nxp.com
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-09-12 11:06:50 +02:00
Jacky Bai
cf6ffb1688 clocksource/drivers/imx-tpm: Fix return -ETIME when delta exceeds INT_MAX
commit 5b8843fcd49827813da80c0f590a17ae4ce93c5d upstream.

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: 059ab7b82e ("clocksource/drivers/imx-tpm: Add imx tpm timer support")
Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Ye Li <ye.li@nxp.com>
Reviewed-by: Jason Liu <jason.hui.liu@nxp.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20240725193355.1436005-1-Frank.Li@nxp.com
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-09-12 11:06:50 +02:00
Anson Huang
ac161f57b6 clocksource/drivers/imx-tpm: Add support for ARM64
Allows building and compile-testing the i.MX TPM driver also
for ARM64. The delay_timer is only supported on ARMv7.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/1585715222-24489-1-git-send-email-Anson.Huang@nxp.com
2020-04-09 16:24:50 +02:00
Anson Huang
55a690f419 clocksource/drivers/imx-tpm: Remove unused includes
There is nothing in use from of_address.h/of_irq.h, remove them.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/1584412549-18354-1-git-send-email-Anson.Huang@nxp.com
2020-03-17 10:10:50 +01:00
Anson Huang
4f352d1fc5 clocksource/drivers/timer-imx-tpm: Specify clock name for timer-of
i.MX TPM needs "ipg" clock for register access and "per" clock for
timer function, the driver gets "ipg" clock by searching the clock
name, but timer-of initialization will get first clock in device
tree TPM node since no clock name specified in of_clk, that means
the "per" clock MUST be the first clock entry in device tree TPM
node, this patch specifies clock name for of_clk to avoid this
restriction, it makes TPM driver work properly with different sequence
of clock entries in device tree TPM node.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2018-12-18 22:22:23 +01:00
Anson Huang
3825603a80 clocksource/drivers/timer-imx-tpm: Convert the driver to timer-of
Convert the driver to use the timer_of helpers.  This allows to handle
timer base, clock and irq using common timer_of driver and it
simplifies the code.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2018-12-18 22:22:23 +01:00
Fabio Estevam
c8437a6cab clocksource/drivers/timer-imx-tpm: Switch to SPDX identifier
Adopt the SPDX license identifier headers to ease license compliance
management.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2018-05-23 07:39:01 +02:00
Anson Huang
7407188489 clocksource/imx-tpm: Correct -ETIME return condition check
The additional brakects added to tpm_set_next_event's return value
computation causes (int) forced type conversion NOT taking effect, and the
incorrect value return will cause various system timer issue, like RCU
stall etc..

Remove the additional brackets to make sure tpm_set_next_event always
returns correct value.

Fixes: 059ab7b82e ("clocksource/drivers/imx-tpm: Add imx tpm timer support")
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Dong Aisheng <Aisheng.dong@nxp.com>
Cc: stable@vger.kernel.org
Cc: daniel.lezcano@linaro.org
Cc: Linux-imx@nxp.com
Link: https://lkml.kernel.org/r/1524117883-2484-1-git-send-email-Anson.Huang@nxp.com
2018-04-19 13:21:35 +02:00
Anson Huang
0136c741ff clocksource/drivers/imx-tpm: Add different counter width support
Different TPM modules have different width counters which is 16-bit or 32-bit,
the counter width can be read from TPM_PARAM register bit[23:16], this patch
adds dynamic check for counter width to support both 16-bit and 32-bit TPM
modules.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2018-03-30 22:44:11 +02:00
Anson Huang
506a7be93f clocksource/drivers/imx-tpm: Correct some registers operation flow
According to i.MX7ULP reference manual, TPM_SC_CPWMS can ONLY be written when
counter is disabled, TPM_SC_TOF is write-1-clear, TPM_C0SC_CHF is also
write-1-clear, correct these registers initialization flow;

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2018-03-30 22:44:11 +02:00
Anson Huang
16328e7bd4 clocksource/drivers/imx-tpm: Fix typo of clock name
The clock name should be ipg instead of igp.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2018-03-30 22:44:10 +02:00
Dong Aisheng
059ab7b82e clocksource/drivers/imx-tpm: Add imx tpm timer support
IMX Timer/PWM Module (TPM) supports both timer and pwm function while
this patch only adds the timer support. PWM would be added later.

The TPM counter, compare and capture registers are clocked by an
asynchronous clock that can remain enabled in low power modes.

NOTE: We observed in a very small probability, the bus fabric
contention between GPU and A7 may results a few cycles delay
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.

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Anson Huang <Anson.Huang@nxp.com>
Cc: Bai Ping <ping.bai@nxp.com>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-08-29 11:07:56 +02:00