Re: [PATCH v1 3/3] arm64: dts: add Hi6220 mailbox node

From: Sudeep Holla
Date: Tue Aug 25 2015 - 07:36:25 EST




On 19/08/15 10:37, Leo Yan wrote:
On Hi6220, below memory regions in DDR have specific purpose:

0x05e0,0000 - 0x05ef,ffff: For MCU firmware using at runtime;
0x0740,f000 - 0x0740,ffff: For MCU firmware's section;
0x06df,f000 - 0x06df,ffff: For mailbox message data.


Unless I am reading the DTS file completely wrong, I don't think the above memory regions are in DDR as per the memory node.

This patch reserves these memory regions and add device node for
mailbox in dts.

Signed-off-by: Leo Yan <leo.yan@xxxxxxxxxx>
---
arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts | 20 +++++++++++++++++---
arch/arm64/boot/dts/hisilicon/hi6220.dtsi | 8 ++++++++
2 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts b/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
index e36a539..d5470d3 100644
--- a/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
+++ b/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
@@ -7,9 +7,6 @@

/dts-v1/;

-/*Reserved 1MB memory for MCU*/
-/memreserve/ 0x05e00000 0x00100000;
-
#include "hi6220.dtsi"

/ {
@@ -28,4 +25,21 @@
device_type = "memory";
reg = <0x0 0x0 0x0 0x40000000>;
};

I have no access to the spec, but I read this as 1GB RAM @0x0
Unless this entry is completely wrong, what your commit log claims is
incorrect. If this entry is wrong I wonder how is it booting with this
DT then.

+
+ reserved-memory {
+ #address-cells = <2>;
+ #size-cells = <2>;
+ ranges;
+
+ mcu-buf@05e00000 {
+ no-map;
+ reg = <0x0 0x05e00000 0x0 0x00100000>, /* MCU firmware buffer */
+ <0x0 0x0740f000 0x0 0x00001000>; /* MCU firmware section */

So I don't see how can this be part of DDR ? Or at-least part of DDR
that's mapped by kernel ?

Regards,
Sudeep
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