| Message ID | alpine.DEB.2.00.1302062343230.12769@utopia.booyaka.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Paul Walmsley <paul@pwsan.com> writes: > On Mon, 4 Feb 2013, Rajendra Nayak wrote: > >> OMAP4 CHIP level PM works only with newer bootloaders. The >> dependency on the bootloader comes from the fact that the >> kernel is missing reset and initialization code for some >> devices. >> >> While the right thing to do is to add reset and init code in >> the kernel, for some co-processor IP blocks like DSP and IVA >> it means downloading firmware into each one of them to execute >> idle instructions. >> >> While a feasible solution is worked upon on how such IP blocks >> can be better handled in the kernel, in the interim, to avoid >> any further frustration to users testing PM on OMAP4 and finding >> it broken, warn them about the bootloader being a possible >> cause. >> >> Signed-off-by: Rajendra Nayak <rnayak@ti.com> >> Cc: Tero Kristo <t-kristo@ti.com> >> Cc: Santosh Shilimkar <santosh.shilimkar@ti.com> >> Cc: R Sricharan <r.sricharan@ti.com> > > Thanks Rajendra, I appreciate the patch. I've tweaked it slightly and the > following is what's queued here; hopefully it can go in for v3.9. > > > - Paul > > From: Rajendra Nayak <rnayak@ti.com> > Date: Mon, 4 Feb 2013 17:54:43 +0530 > Subject: [PATCH] ARM: OMAP4: PM: Warn users about usage of older bootloaders > > OMAP4 CHIP level PM works only with newer bootloaders. The > dependency on the bootloader comes from the fact that the > kernel is missing reset and initialization code for some > devices. > > While the right thing to do is to add reset and init code in > the kernel, for some co-processor IP blocks like DSP and IVA > it means downloading firmware into each one of them to execute > idle instructions. > > While a feasible solution is worked upon on how such IP blocks > can be better handled in the kernel, in the interim, to avoid > any further frustration to users testing PM on OMAP4 and finding > it broken, warn them about the bootloader being a possible > cause. > > Signed-off-by: Rajendra Nayak <rnayak@ti.com> > Cc: Tero Kristo <t-kristo@ti.com> > Cc: Santosh Shilimkar <santosh.shilimkar@ti.com> > Cc: R Sricharan <r.sricharan@ti.com> > [paul@pwsan.com: tweaked warning messages and comments slightly] > Signed-off-by: Paul Walmsley <paul@pwsan.com> FWIW Acked-by: Kevin Hilman <khilman@linaro.org> > --- > arch/arm/mach-omap2/pm44xx.c | 19 ++++++++++++++++++- > 1 file changed, 18 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/mach-omap2/pm44xx.c b/arch/arm/mach-omap2/pm44xx.c > index aa6fd98..502ed9b 100644 > --- a/arch/arm/mach-omap2/pm44xx.c > +++ b/arch/arm/mach-omap2/pm44xx.c > @@ -77,8 +77,18 @@ static int omap4_pm_suspend(void) > omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state); > pwrdm_set_logic_retst(pwrst->pwrdm, pwrst->saved_logic_state); > } > - if (ret) > + if (ret) { > pr_crit("Could not enter target state in pm_suspend\n"); > + /* > + * OMAP4 chip PM currently works only with certain (newer) > + * versions of bootloaders. This is due to missing code in the > + * kernel to properly reset and initialize some devices. > + * Warn the user about the bootloader version being one of the > + * possible causes. > + * http://www.spinics.net/lists/arm-kernel/msg218641.html > + */ > + pr_warn("A possible cause could be an old bootloader - try u-boot >= v2012.07\n"); > + } > else > pr_info("Successfully put all powerdomains to target state\n"); > > @@ -146,6 +156,13 @@ int __init omap4_pm_init(void) > } > > pr_err("Power Management for TI OMAP4.\n"); > + /* > + * OMAP4 chip PM currently works only with certain (newer) > + * versions of bootloaders. This is due to missing code in the > + * kernel to properly reset and initialize some devices. > + * http://www.spinics.net/lists/arm-kernel/msg218641.html > + */ > + pr_warn("u-boot >= v2012.07 is required for full PM support\n"); > > ret = pwrdm_for_each(pwrdms_setup, NULL); > if (ret) {
diff --git a/arch/arm/mach-omap2/pm44xx.c b/arch/arm/mach-omap2/pm44xx.c index aa6fd98..502ed9b 100644 --- a/arch/arm/mach-omap2/pm44xx.c +++ b/arch/arm/mach-omap2/pm44xx.c @@ -77,8 +77,18 @@ static int omap4_pm_suspend(void) omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state); pwrdm_set_logic_retst(pwrst->pwrdm, pwrst->saved_logic_state); } - if (ret) + if (ret) { pr_crit("Could not enter target state in pm_suspend\n"); + /* + * OMAP4 chip PM currently works only with certain (newer) + * versions of bootloaders. This is due to missing code in the + * kernel to properly reset and initialize some devices. + * Warn the user about the bootloader version being one of the + * possible causes. + * http://www.spinics.net/lists/arm-kernel/msg218641.html + */ + pr_warn("A possible cause could be an old bootloader - try u-boot >= v2012.07\n"); + } else pr_info("Successfully put all powerdomains to target state\n"); @@ -146,6 +156,13 @@ int __init omap4_pm_init(void) } pr_err("Power Management for TI OMAP4.\n"); + /* + * OMAP4 chip PM currently works only with certain (newer) + * versions of bootloaders. This is due to missing code in the + * kernel to properly reset and initialize some devices. + * http://www.spinics.net/lists/arm-kernel/msg218641.html + */ + pr_warn("u-boot >= v2012.07 is required for full PM support\n"); ret = pwrdm_for_each(pwrdms_setup, NULL); if (ret) {