Re: [PATCH 3/3] 8250: add workaround for MPC8[356]xx UART break IRQ storm

From: Kumar Gala
Date: Thu Dec 01 2011 - 19:18:11 EST



On Dec 1, 2011, at 6:05 PM, Paul Gortmaker wrote:

> On 11-12-01 06:51 PM, Scott Wood wrote:
>> On 12/01/2011 05:47 PM, Paul Gortmaker wrote:
>>> diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
>>> index 8c660af..b0f4042 100644
>>> --- a/include/linux/serial_8250.h
>>> +++ b/include/linux/serial_8250.h
>>> @@ -18,6 +18,11 @@
>>> #define UART_BUG_TXEN (1 << 1) /* buggy TX IIR status */
>>> #define UART_BUG_NOMSR (1 << 2) /* buggy MSR status bits (Au1x00) */
>>> #define UART_BUG_THRE (1 << 3) /* buggy THRE reassertion */
>>> +#ifdef CONFIG_PPC32
>>> +#define UART_BUG_FSLBK (1 << 4) /* buggy FSL break IRQ storm */
>>> +#else /* help GCC optimize away IRQ handler errata code for ARCH != PPC32 */
>>> +#define UART_BUG_FSLBK 0
>>> +#endif
>>
>> I believe this bug still exists on our 64-bit chips.
>
> OK, I'll simply change the above to CONFIG_PPC then.

It does, the bug is in the uart IP which I don't think we ever plan on fixing, so 32 or 64-bit parts will have it for ever and ever ;)

- k--
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