On 24.4.2018 14:49, Lokesh Vutla wrote:
Hi Michal,
On Tuesday 24 April 2018 05:54 PM, Michal Simek wrote:
Hi,
On 24.4.2018 06:45, Lokesh Vutla wrote:
Hi Michal,
On Monday 23 April 2018 11:56 AM, Michal Simek wrote:
On 23.4.2018 05:53, Lokesh Vutla wrote:
On Friday 20 April 2018 07:21 PM, Michal Simek wrote:
This minimal support will be used by Xilinx ZynqMP R5 cpu.
Signed-off-by: Michal Simek michal.simek@xilinx.com
arch/arm/Kconfig | 6 ++++++ arch/arm/cpu/armv7r/Makefile | 4 ++++ arch/arm/cpu/armv7r/config.mk | 3 +++ arch/arm/cpu/armv7r/cpu.c | 24 ++++++++++++++++++++++++ arch/arm/cpu/armv7r/start.S | 17 +++++++++++++++++ 5 files changed, 54 insertions(+) create mode 100644 arch/arm/cpu/armv7r/Makefile create mode 100644 arch/arm/cpu/armv7r/config.mk create mode 100644 arch/arm/cpu/armv7r/cpu.c create mode 100644 arch/arm/cpu/armv7r/start.S
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index b5fbce03667d..b10804f55224 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -192,6 +192,10 @@ config CPU_V7M select THUMB2_KERNEL select SYS_CACHE_SHIFT_5
+config CPU_V7R
- bool
- select SYS_CACHE_SHIFT_6
select HAS_THUMB2 might be a good option?
I didn't enable it because I didn't test it. It can be added when someone tests this.
config CPU_PXA bool select SYS_CACHE_SHIFT_5 @@ -209,6 +213,7 @@ config SYS_CPU default "arm1176" if CPU_ARM1176 default "armv7" if CPU_V7 default "armv7m" if CPU_V7M
- default "armv7r" if CPU_V7R default "pxa" if CPU_PXA default "sa1100" if CPU_SA1100 default "armv8" if ARM64
@@ -223,6 +228,7 @@ config SYS_ARM_ARCH default 6 if CPU_ARM1176 default 7 if CPU_V7 default 7 if CPU_V7M
- default 7 if CPU_V7R default 5 if CPU_PXA default 4 if CPU_SA1100 default 8 if ARM64
I did a grep of CPU_V7, and you might want to update for CPU_V7R in the following places:
diff --git a/arch/arm/Makefile b/arch/arm/Makefile index 4fa8b38397..f4bc1f250d 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -18,6 +18,7 @@ arch-$(CONFIG_CPU_ARM1136) =-march=armv5 arch-$(CONFIG_CPU_ARM1176) =-march=armv5t arch-$(CONFIG_CPU_V7) =$(call cc-option, -march=armv7-a, \ $(call cc-option, -march=armv7, -march=armv5)) +arch-$(CONFIG_CPU_V7R) =-march=armv7-r
I have setup PLATFORM_CPPFLAGS via config.mk
If both options are selected I am getting this compilation warning. cc1: warning: switch -mcpu=cortex-r5 conflicts with -march=armv7-r switch
hmm..that's strange. I guess it should be reported to gcc? Something similar has been reported for a15 as well[1].
But looking at the implementation of armv7 we just included march. may be we should stick to it?
As I said I have not a problem to add there -march=armv7-r instead of -mcpu=cortex-r5.
Not sure which one is better or if it is better to have this arch flag via this makefile or as platform cppflags via config.mk. I choose the second option because it seems to me better if this is in subfolder. But not a problem to use different flag and put it to this Makefile.
The same style is used for cpu_v7m.
v7-r is very much close to v7. I would prefer to compare with v7 implementation than v7-m :)
I started with symlink to v7. And I didn't play with MPU. Anyway both ways works for me.
arch-$(CONFIG_ARM64) =-march=armv8-a
# On Tegra systems we must build SPL for the armv4 core on the device @@ -41,6 +42,7 @@ tune-$(CONFIG_CPU_PXA) =-mcpu=xscale tune-$(CONFIG_CPU_ARM1136) = tune-$(CONFIG_CPU_ARM1176) = tune-$(CONFIG_CPU_V7) = +tune-$(CONFIG_CPU_V7R) =
Again as above. I used v7m as pattern and there is also empty tune parameter. Is there any good reason to have it empty?
tune-$(CONFIG_ARM64) =
# Evaluate tune cc-option calls now
diff --git a/arch/arm/cpu/armv7r/Makefile b/arch/arm/cpu/armv7r/Makefile new file mode 100644 index 000000000000..3c66976dfa62 --- /dev/null +++ b/arch/arm/cpu/armv7r/Makefile
hmm..do we really need to create a separate folder? IIUC, the main difference between V7 and V7R is MMU vs MPU. IMHO, we should be able to get it using Kconfigs.
I have used V7 for the initial port and then was checking V7M which is already there and used it as pattern for writing this patch.
I have debugged V7 and found that I need to disable CONFIG_HAS_VBAR that's why I have created new symbol as for V7M.
We should be able to create a kconfig symbol for that and select accordingly. Kernel does it the same way.
What kernel Kconfig option are you talking about? (I didn't look at Linux running on R5 but it is reasonable step).
It is really a question if adding new Kconfig symbol for VBAR is the right thing to do. I would need to add VBAR to every platform which has CPU_V7.
Definitely I am open to hear your suggestion
I just did a couple of quick experiments and able to get v7-r support along with v7 support. let me know if you would like to take a look at it. Then Ill pick your patch 1/2 and post the series.
I am definitely confident that this will work because I used that in past. Definitely feel free to send it and I will take a look at retest on R5.
Sorry, I did not mean this patch does not work. It definitely works. I am trying to tell that with some kconfig changes we should be able to re-use armv7 folder instead of creating new folder. Apologies if my reply has communicated wrongly.
I know that it will work. Please send it and I will take a look. The same is for v7m which can be also squashed with v7 + some Kconfig options.
Thanks, Michal