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Re: [PATCH v2 4/4] ARM: bcm2835: Switch to using the new clock driver support.

From Stephen Warren <swarren@wwwdotorg.org>
Newsgroups linux.kernel
Subject Re: [PATCH v2 4/4] ARM: bcm2835: Switch to using the new clock driver support.
Date 2015-09-22 04:10 +0200
Message-ID <qblbP-8bk-3@gated-at.bofh.it> (permalink)
References <q7i2R-5S9-9@gated-at.bofh.it> <q7i2S-5S9-23@gated-at.bofh.it>
Organization linux.* mail to news gateway

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On 09/10/2015 02:58 PM, Eric Anholt wrote:
> This will give us the ability to set the pixel and HDMI state machine
> clocks for the VC4 KMS driver, change the CPU frequency, and
> potentially gate clocks in the future (once we also write a power
> domain driver).  It also gives the uart an explicit clock reference,
> so that we don't need to change the physical addresses of the old
> fixed clk_bcm2835.c clocks for Raspberry Pi 2 port.
> 
> Two clocks get their frequencies updated as a result of this.  One is
> uart's apb_pclk, which was previously accidentally grabbing the fixed
> uart0_pclk due to the apb_pclk not having clk_register_clkdev()
> called.  The uart doesn't seem to do anything with apb_pclk other than
> make sure it's on, so that appears safe (also, as far as I can see,
> the apb clock is actually the same as the VPU clock).  The other is
> EMMC, which according to the docs was supposed to be in the 50-100Mhz
> range, but it turns out the firmware needed to change to running it at
> the 250Mhz core clock speed to avoid a bug in clock domain crossing.
> 
> Additionally, anything using BCM2835_CLOCK_VPU will now have a correct
> clock rate if the user configures the boot-time core clock speed using
> config.txt.

Acked-by: Stephen Warren <swarren@wwwdotorg.org>
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Thread

[PATCH v2 1/4] clk: bcm2835: Move under bcm/ with other Broadcom SoC clk drivers. Eric Anholt <eric@anholt.net> - 2015-09-11 00:00 +0200
  [PATCH v2 2/4] clk: bcm2835: Add binding docs for the new platform clock driver. Eric Anholt <eric@anholt.net> - 2015-09-11 00:00 +0200
    Re: [PATCH v2 2/4] clk: bcm2835: Add binding docs for the new  platform clock driver. Stephen Warren <swarren@wwwdotorg.org> - 2015-09-22 04:10 +0200
  [PATCH v2 4/4] ARM: bcm2835: Switch to using the new clock driver support. Eric Anholt <eric@anholt.net> - 2015-09-11 00:00 +0200
    Re: [PATCH v2 4/4] ARM: bcm2835: Switch to using the new clock driver  support. Stephen Warren <swarren@wwwdotorg.org> - 2015-09-22 04:10 +0200
  Re: [PATCH v2 3/4] clk: bcm2835: Add support for programming the audio domain clocks. Martin Sperl <martin@sperl.org> - 2015-09-11 12:10 +0200
  Re: [PATCH v2 3/4] clk: bcm2835: Add support for programming the  audio domain clocks. Stephen Warren <swarren@wwwdotorg.org> - 2015-09-22 04:10 +0200
    Re: [PATCH v2 3/4] clk: bcm2835: Add support for programming the audio domain clocks. Eric Anholt <eric@anholt.net> - 2015-09-28 23:20 +0200

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