Messages in this thread | | | From | Peng Fan <> | Subject | RE: [PATCH] clk: imx: imx8qxp-lpcg: use devm_platform_ioremap_resource | Date | Thu, 5 Dec 2019 09:03:26 +0000 |
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> Subject: Re: [PATCH] clk: imx: imx8qxp-lpcg: use > devm_platform_ioremap_resource > > On 2019-12-05 3:38 AM, Peng Fan wrote: > >> Subject: Re: [PATCH] clk: imx: imx8qxp-lpcg: use > >> devm_platform_ioremap_resource > >> > >> On 2019-12-04 12:14 PM, Peng Fan wrote: > >>> From: Peng Fan <peng.fan@nxp.com> > >>> > >>> devm_platform_ioremap_resource() wraps platform_get_resource() and > >>> devm_ioremap_resource(), we could use this API to simplify the code. > >>> > >>> Signed-off-by: Peng Fan <peng.fan@nxp.com> > >> > >> This patch has been posted before and it breaks uart on imx8qxp-mek > >> and possibly other things. > >> > >> The old and new paths are not equivalent: > >> devm_platform_ioremap_resource calls devm_ioremap_resource differs > >> from devm_ioremap by also calling devm_request_mem_region. > >> > >> This prevents other mappings in the area; this is not an issue for > >> most drivers but imx8qxp-lpcg maps whole subsystems. For example: > >> > >> adma_lpcg: clock-controller@59000000 { > >> compatible = "fsl,imx8qxp-lpcg-adma"; > >> reg = <0x59000000 0x2000000>; > >> #clock-cells = <1>; > >> }; > >> > >> adma_lpuart0: serial@5a060000 { > >> reg = <0x5a060000 0x1000>; > >> ... > >> }; > >> > >> Previously: https://patchwork.kernel.org/patch/10908807/ > > > > Thanks. I think at least need to provide some comments in code. > > Yes, comments would help. I think it's actually the 3rd time this incorrect > cleanup was posted. > > But mapping entire subsystems (32mb at a time) for LPCG is deeply > flawed: the LPCG areas are each 64k and they're interspersed among the > peripherals. The correct solution is to have many small clock providers. > > This is done by a series of patches from Aisheng, I think this is the latest one: > > https://patchwork.kernel.org/patch/11248235/ > > If some aspects of that series are dubious perhaps they could be discussed > and maybe the series could be split into smaller chunks?
That would be lots of lpcg nodes in device tree.
> > That series does brings many essential improvements to imx8 clk support.
Seems that pending for long time? What is the blocking point?
Regards, Peng.
> > -- > Regards, > Leonard
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