Message ID | 20221110114549.34121-1-steven.price@arm.com |
---|---|
State | Accepted |
Headers | show |
Series | pwm: tegra: Fix 32 bit build | expand |
On 10/11/2022 11:45, Steven Price wrote: > The value of NSEC_PER_SEC << PWM_DUTY_WIDTH doesn't fix within a 32 bit > integer causing a build warning/error (and the value truncated): > > drivers/pwm/pwm-tegra.c: In function ‘tegra_pwm_config’: > drivers/pwm/pwm-tegra.c:148:53: error: result of ‘1000000000 << 8’ requires 39 bits to represent, but ‘long int’ only has 32 bits [-Werror=shift-overflow=] > 148 | required_clk_rate = DIV_ROUND_UP_ULL(NSEC_PER_SEC << PWM_DUTY_WIDTH, > | ^~ > > Explicitly cast to a u64 to ensure the correct result. > > Fixes: cfcb68817fb3 ("pwm: tegra: Improve required rate calculation") > Signed-off-by: Steven Price <steven.price@arm.com> > --- > drivers/pwm/pwm-tegra.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c > index 6fc4b69a3ba7..249dc0193297 100644 > --- a/drivers/pwm/pwm-tegra.c > +++ b/drivers/pwm/pwm-tegra.c > @@ -145,7 +145,7 @@ static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, > * source clock rate as required_clk_rate, PWM controller will > * be able to configure the requested period. > */ > - required_clk_rate = DIV_ROUND_UP_ULL(NSEC_PER_SEC << PWM_DUTY_WIDTH, > + required_clk_rate = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC << PWM_DUTY_WIDTH, > period_ns); > > if (required_clk_rate > clk_round_rate(pc->clk, required_clk_rate)) Thanks! Reviewed-by: Jon Hunter <jonathanh@nvidia.com> Jon
Hello, On Thu, Nov 10, 2022 at 11:45:48AM +0000, Steven Price wrote: > The value of NSEC_PER_SEC << PWM_DUTY_WIDTH doesn't fix within a 32 bit > integer causing a build warning/error (and the value truncated): > > drivers/pwm/pwm-tegra.c: In function ‘tegra_pwm_config’: > drivers/pwm/pwm-tegra.c:148:53: error: result of ‘1000000000 << 8’ requires 39 bits to represent, but ‘long int’ only has 32 bits [-Werror=shift-overflow=] > 148 | required_clk_rate = DIV_ROUND_UP_ULL(NSEC_PER_SEC << PWM_DUTY_WIDTH, > | ^~ > > Explicitly cast to a u64 to ensure the correct result. Hmm, ideally this should have popped up earlier :-\ Anyhow: Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Thanks Uwe
On Thu, 10 Nov 2022 11:45:48 +0000, Steven Price wrote: > The value of NSEC_PER_SEC << PWM_DUTY_WIDTH doesn't fix within a 32 bit > integer causing a build warning/error (and the value truncated): > > drivers/pwm/pwm-tegra.c: In function ‘tegra_pwm_config’: > drivers/pwm/pwm-tegra.c:148:53: error: result of ‘1000000000 << 8’ requires 39 bits to represent, but ‘long int’ only has 32 bits [-Werror=shift-overflow=] > 148 | required_clk_rate = DIV_ROUND_UP_ULL(NSEC_PER_SEC << PWM_DUTY_WIDTH, > | ^~ > > [...] Applied, thanks! [1/1] pwm: tegra: Fix 32 bit build commit: dd1f1da4ada5d8ac774c2ebe97230637820b3323 Best regards,
diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c index 6fc4b69a3ba7..249dc0193297 100644 --- a/drivers/pwm/pwm-tegra.c +++ b/drivers/pwm/pwm-tegra.c @@ -145,7 +145,7 @@ static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, * source clock rate as required_clk_rate, PWM controller will * be able to configure the requested period. */ - required_clk_rate = DIV_ROUND_UP_ULL(NSEC_PER_SEC << PWM_DUTY_WIDTH, + required_clk_rate = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC << PWM_DUTY_WIDTH, period_ns); if (required_clk_rate > clk_round_rate(pc->clk, required_clk_rate))
The value of NSEC_PER_SEC << PWM_DUTY_WIDTH doesn't fix within a 32 bit integer causing a build warning/error (and the value truncated): drivers/pwm/pwm-tegra.c: In function ‘tegra_pwm_config’: drivers/pwm/pwm-tegra.c:148:53: error: result of ‘1000000000 << 8’ requires 39 bits to represent, but ‘long int’ only has 32 bits [-Werror=shift-overflow=] 148 | required_clk_rate = DIV_ROUND_UP_ULL(NSEC_PER_SEC << PWM_DUTY_WIDTH, | ^~ Explicitly cast to a u64 to ensure the correct result. Fixes: cfcb68817fb3 ("pwm: tegra: Improve required rate calculation") Signed-off-by: Steven Price <steven.price@arm.com> --- drivers/pwm/pwm-tegra.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)