Messages in this thread | | | Date | Thu, 7 Apr 2011 09:30:15 +0200 | From | Mattias Wallin <> | Subject | Re: [PATCHv5 2/3] ARM: Allow machines to override __delay() |
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On 04/06/2011 01:56 AM, Stephen Boyd wrote: > Some machines want to implement their own __delay() routine based > on fixed rate timers. Expose functionality to set the __delay() > routine at runtime. This should allow two machines with different > __delay() routines to happily co-exist within the same kernel > with minimal overhead. > > Russell expressed concern that using a timer based __delay() > would cause problems when an iomapped device isn't mapped in > prior to a delay call being made (see > http://article.gmane.org/gmane.linux.ports.arm.kernel/78543 for > more info). We can sidestep that issue with this approach since > the __delay() routine_should_ only be pointed to a timer based > delay once the timer has been properly mapped. Up until that > point __delay() and udelay() will use delay_loop() which is > always safe to call. > > This patch is inspired by x86's delay.c >
Tested-by: Mattias Wallin <mattias.wallin@stericsson.com>
Yours, Mattias Wallin
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