* Darrick J. Wong <djwong@xxxxxxxxxx> wrote: > On Fri, May 15, 2009 at 12:12:19PM -0700, Darrick J. Wong wrote: > > On Thu, Apr 30, 2009 at 12:13:38PM +0100, Matthew Garrett wrote: > > > On Thu, Apr 30, 2009 at 01:10:42PM +0200, Ingo Molnar wrote: > > > > > > > thanks - i've applied this and started testing it. I suspect 1-2 > > > > days of test-time should be enough to see if it breaks this box in > > > > any way. > > > > > > My recollection was that you'd see the machine limited to 1GHz on every > > > boot? > > > > That seems accurate based on my reading of the old thread. > > > > It's been a couple of weeks; has anyone seen any problems? > > Now it's been thirty days since I last heard from anyone. Has the > problem been fixed by some other means? I see no problems on that system here, with the patch below applied. So, as i indicated above, feel free to pursue this angle, there's no objection from me. Thanks, Ingo -------------> >From 244b66ac1fbbe25262a9bcc28179e50930290de8 Mon Sep 17 00:00:00 2001 From: Matthew Garrett <mjg59@xxxxxxxxxxxxx> Date: Thu, 30 Apr 2009 10:54:14 +0100 Subject: [PATCH] acpi: Fix regression where _PPC is not read at boot even when ignore_ppc=0 Earlier, Ingo Molnar posted a patch to make it so that the kernel would avoid reading _PPC on his broken T60. Unfortunately, it seems that with Thomas Renninger's patch last July to eliminate _PPC evaluations when the processor driver loads, the kernel never actually reads _PPC at all! This is problematic if you happen to boot your non-T60 computer in a state where the BIOS _wants_ _PPC to be something other than zero. So, put the _PPC evaluation back into acpi_processor_get_performance_info if ignore_ppc isn't 1. This second version restores the correct function call, which simplifies the patch. I apologize for the churn and the poor eyesight. Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx> Cc: "Darrick J. Wong" <djwong@xxxxxxxxxx> Cc: Thomas Renninger <trenn@xxxxxxx> LKML-Reference: <20090430095414.GA19462@xxxxxxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxx> --- drivers/acpi/processor_perflib.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/drivers/acpi/processor_perflib.c b/drivers/acpi/processor_perflib.c index cafb410..85af717 100644 --- a/drivers/acpi/processor_perflib.c +++ b/drivers/acpi/processor_perflib.c @@ -348,7 +348,11 @@ static int acpi_processor_get_performance_info(struct acpi_processor *pr) if (result) goto update_bios; - return 0; + /* We need to call _PPC once when cpufreq starts */ + if (ignore_ppc != 1) + result = acpi_processor_get_platform_limit(pr); + + return result; /* * Having _PPC but missing frequencies (_PSS, _PCT) is a very good hint that -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
