Re: [PATCH] m68k/mvme16x: Fix timer interrupts

[Finn Thain <fthain@telegraphics.com.au>]

On Tue, 16 Mar 2021, Mike Pavone wrote:

> Timer interrupts on MVME16x and MVME17x boards are broken as the CEN and
> COC bits are being inadvertently cleared when clearing the overflow
> counter. This results in no timer interrupts being delivered after the
> first. Initialization then hangs in calibrate_delay as the jiffies counter
> is not updated. OR with current register value to preserve these bits.
> 
> Fixes: 19999a8b8782 ("m68k: mvme16x: Handle timer counter overflow")
> Signed-off-by: Michael Pavone <pavone@retrodev.com>

Sorry about that regression.

Do you think that commit 7529b90d051e ("m68k: mvme147: Handle timer 
counter overflow") has the same problem?

> ---
>  arch/m68k/mvme16x/config.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/m68k/mvme16x/config.c b/arch/m68k/mvme16x/config.c
> index 30357fe4ba6c..949d3e19f79c 100644
> --- a/arch/m68k/mvme16x/config.c
> +++ b/arch/m68k/mvme16x/config.c
> @@ -375,7 +375,7 @@ static irqreturn_t mvme16x_timer_int (int irq, void
> *dev_id)
>   	local_irq_save(flags);
>  	out_8(PCCTIC1, in_8(PCCTIC1) | PCCTIC1_INT_CLR);
> -	out_8(PCCTOVR1, PCCTOVR1_OVR_CLR);
> +	out_8(PCCTOVR1, in_8(PCCTOVR1) | PCCTOVR1_OVR_CLR);
>  	clk_total += PCC_TIMER_CYCLES;
>  	legacy_timer_tick(1);
>  	local_irq_restore(flags);
> 
>