Re: [PATCH V4 1/3] ARM: dts: Add pmu sysreg node to Exynos5 dtsi file

On Wednesday 30 of October 2013 15:43:19 Sachin Kamat wrote:

On 30 October 2013 15:39, Leela Krishna Amudala [off-list ref] wrote:

quoted

Hi,

On Wed, Oct 30, 2013 at 3:22 PM, Sachin Kamat [off-list ref] wrote:

quoted

Hi Leela,

On 30 October 2013 15:21, Leela Krishna Amudala [off-list ref] wrote:

quoted

This patch adds pmusysreg node to Exynos5 dtsi file to handle PMU
register accesses in a centralized way using syscon driver

Signed-off-by: Leela Krishna Amudala <redacted>
---
 arch/arm/boot/dts/exynos5.dtsi |    5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/exynos5.dtsi b/arch/arm/boot/dts/exynos5.dtsi
index e52b038..918e732 100644
--- a/arch/arm/boot/dts/exynos5.dtsi
+++ b/arch/arm/boot/dts/exynos5.dtsi

@@ -106,4 +106,9 @@
                #size-cells = <0>;
                status = "disabled";
        };
+
+       pmu_sys_reg: pmusysreg@1004000 {
+               compatible = "syscon";
+               reg = <0x10040000 0x5000>;
+       };
 };

Had a look at this in a bit detail and found the following.
The register base address for this block on 5250 and 5420 as per the
TRM is 0x10050000.

Also, the binding document specifies the naming convention. According
to it this node
should like:

sys_reg: sysreg@10050000 {
           compatible = "samsung,exynos5-sysreg", "syscon";
           reg = <0x10050000 0x500>;
};

I know, but here my intention is not to regmap system register (0x10050000),
but instead PMU register (0x10040000), Hence created this node.

This clashes with the existing binding for this type of node. Probably
you will need to
define it differently?

PMU and System Registers are two completely separate entities. However
a generic syscon binding can be used to represent both, because they are
just collections of registers shared by multiple IPs.

Best regards,
Tomasz