[PATCH 0/4] Add framework to support clkout
pankaj.dubey at samsung.com
Fri May 9 20:39:52 PDT 2014
On 05/09/2014 10:00 PM, Tushar Behera wrote:
> The MUX/GATE register for XCLKOUT doesn't resides within PMU domain,
> this can be accessed through a regmap provided by syscon driver. Adding
> another clock provider to handle regmap based handing of XCLKOUT.
> 1. [PATCH v3] mfd: syscon: Support early initialization
> Also we need to find a suitable place to call early_syscon_init(), after
> the device tree has been unflattened and before clock initialization.
> While testing, I called this before of_clk_init() in arch/arm/kernel/time.c,
> but that place is too generic. Calling anywhere from exynos.c is not
> working ATM.
IMO we do not need to, or if I am not wrong we should not change time.c.
It's possible if we have exynos specific init_time with following changes.
FYI, In my patch series for Exynos PMU , currently I am handling this in
exynos_dt_machine_init. But definitely it can be handled as below and it works
without any side effect and I have tested it. Only reason I do not adopted this
as for Exynos PMU patch support I had other options. But if required and if
following change is acceptable I can include this in my next version of Exynos
PMU patch series.
+static void __init exynos_init_time(void)
+ /* Nothing to do timer specific
+ * as early_syscon_init requires DT to be unflattened and
+ * system should be able to allocate memory we need to
+ * postpone until init_time, but it should be done before
+ * init_machine. Because before init_machine, secondary
+ * core boot starts and it uses PMU registers.
DT_MACHINE_START(EXYNOS_DT, "SAMSUNG EXYNOS (Flattened Device Tree)")
/* Maintainer: Thomas Abraham <thomas.abraham at linaro.org> */
/* Maintainer: Kukjin Kim <kgene.kim at samsung.com> */
.smp = smp_ops(exynos_smp_ops),
.map_io = exynos_init_io,
.init_early = exynos_firmware_init,
+ .init_time = exynos_init_time,
> Tushar Behera (4):
> clk: samsung: out: Add infrastructure to register CLKOUT
> clk: samsung: exynos5420: Add xclkout debug clock
> clk: samsung: exynos5250: Add xclkout debug clock
> ARM: dts: Add pmu-syscon handle for Exynos5420/Exynos5250 clock
> arch/arm/boot/dts/exynos5250.dtsi | 1 +
> arch/arm/boot/dts/exynos5420.dtsi | 1 +
> drivers/clk/samsung/Makefile | 2 +-
> drivers/clk/samsung/clk-exynos5250.c | 14 +++
> drivers/clk/samsung/clk-exynos5420.c | 14 +++
> drivers/clk/samsung/clk-out.c | 181 ++++++++++++++++++++++++++++++++
> drivers/clk/samsung/clk.h | 33 ++++++
> include/dt-bindings/clock/exynos5250.h | 3 +
> include/dt-bindings/clock/exynos5420.h | 5 +-
> 9 files changed, 252 insertions(+), 2 deletions(-)
> create mode 100644 drivers/clk/samsung/clk-out.c
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