Messages in this thread | | | Subject | Re: [PATCH v2 3/4] clk: bcm2835: Add support for programming the audio domain clocks. | From | Martin Sperl <> | Date | Fri, 11 Sep 2015 12:08:21 +0200 |
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> On 10.09.2015, at 23:58, Eric Anholt <eric@anholt.net> wrote: > > This adds support for enabling, disabling, and setting the rate of the > audio domain clocks. It will be necessary for setting the pixel clock > for HDMI in the VC4 driver and let us write a cpufreq driver. It will > also improve compatibility with user changes to the firmware's > config.txt, since our previous fixed clocks are unaware of it. > > The firmware also has support for configuring the clocks through the > mailbox channel, but the pixel clock setup by the firmware doesn't > work, and it's Raspberry Pi specific anyway. The only conflicts we > should have with the firmware would be if we made firmware calls that > result in clock management (like opening firmware V3D or ISP access, > which we don't support in upstream), or on hardware over-thermal or > under-voltage (when the firmware would rewrite PLLB to take the ARM > out of overclock). If that happens, our cached .recalc_rate() results > would be incorrect, but that's no worse than our current state where > we used fixed clocks. > > The existing fixed clocks in the code are left in place to provide > backwards compatibility with old device tree files. > > Signed-off-by: Eric Anholt <eric@anholt.net>
This patch-sets sets the emmc clock to correct frequency - no longer overclocking SDCards by a factor of 2.5. This means booting from the eMMC on the Compute module works now without issues.
Note that the DT bcm2835-rpi-b-plus.dtb can get used to boot the compute module.
Thanks
Tested-by: Martin Sperl <kernel@martin.sperl.org>
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