clk: shmobile: rz: Add CPG/MSTP Clock Domain support

Add Clock Domain support to the RZ Clock Pulse Generator (CPG) driver
using the generic PM Domain.  This allows to power-manage the module
clocks of SoC devices that are part of the CPG/MSTP Clock Domain using
Runtime PM, or for system suspend/resume.

SoC devices that are part of the CPG/MSTP Clock Domain and can be
power-managed through an MSTP clock should be tagged in DT with a proper
"power-domains" property.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
This commit is contained in:
Geert Uytterhoeven 2015-08-04 14:28:06 +02:00 committed by Simon Horman
parent 63e05d9365
commit f04b486d34
3 changed files with 31 additions and 2 deletions

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@ -2,6 +2,8 @@
The CPG generates core clocks for the RZ SoCs. It includes the PLL, variable
CPU and GPU clocks, and several fixed ratio dividers.
The CPG also provides a Clock Domain for SoC devices, in combination with the
CPG Module Stop (MSTP) Clocks.
Required Properties:
@ -14,10 +16,18 @@ Required Properties:
- #clock-cells: Must be 1
- clock-output-names: The names of the clocks. Supported clocks are "pll",
"i", and "g"
- #power-domain-cells: Must be 0
SoC devices that are part of the CPG/MSTP Clock Domain and can be power-managed
through an MSTP clock should refer to the CPG device node in their
"power-domains" property, as documented by the generic PM domain bindings in
Documentation/devicetree/bindings/power/power_domain.txt.
Example
-------
Examples
--------
- CPG device node:
cpg_clocks: cpg_clocks@fcfe0000 {
#clock-cells = <1>;
@ -26,4 +36,19 @@ Example
reg = <0xfcfe0000 0x18>;
clocks = <&extal_clk>, <&usb_x1_clk>;
clock-output-names = "pll", "i", "g";
#power-domain-cells = <0>;
};
- CPG/MSTP Clock Domain member device node:
mtu2: timer@fcff0000 {
compatible = "renesas,mtu2-r7s72100", "renesas,mtu2";
reg = <0xfcff0000 0x400>;
interrupts = <0 107 IRQ_TYPE_LEVEL_HIGH>;
interrupt-names = "tgi0a";
clocks = <&mstp3_clks R7S72100_CLK_MTU2>;
clock-names = "fck";
power-domains = <&cpg_clocks>;
status = "disabled";
};

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@ -51,6 +51,7 @@ config ARCH_EMEV2
config ARCH_R7S72100
bool "RZ/A1H (R7S72100)"
select PM_GENERIC_DOMAINS if PM
select SYS_SUPPORTS_SH_MTU2
config ARCH_R8A73A4

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@ -10,6 +10,7 @@
*/
#include <linux/clk-provider.h>
#include <linux/clk/shmobile.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/of.h>
@ -99,5 +100,7 @@ static void __init rz_cpg_clocks_init(struct device_node *np)
}
of_clk_add_provider(np, of_clk_src_onecell_get, &cpg->data);
cpg_mstp_add_clk_domain(np);
}
CLK_OF_DECLARE(rz_cpg_clks, "renesas,rz-cpg-clocks", rz_cpg_clocks_init);