Re: [v0 PATCH 5/5] EDAC: CPC925 MC platform device setup

From: Harry Ciao
Date: Fri Apr 03 2009 - 01:55:21 EST


Harry Ciao åé:
Arnd Bergmann åé:
On Thursday 02 April 2009, Harry Ciao wrote:
+#ifdef CONFIG_EDAC
+#define CPC925_MC_START 0xf8000000
+#define CPC925_MC_END 0xf8ffffff /* sizeof 16MB */
+/* Register a platform device for CPC925 memory controller */
+static int __init maple_cpc925_edac_setup(void)

It's not good to have these encoded as magic numbers.
Can't you find the addresses in the device tree? Maybe it's
even possible to make this an of_platform_driver if you
find a good node to bind to.

Does the driver also work on a G5 Mac, or is it limited
to the maple platform?

Arnd <><

Hi Arnd,

I forgot to mention that so far I have tested this CPC925 driver on the Maple platform, I have no G5 Mac to test with.
CPC925 is specific to the PowerPC 970 family of processors, but I don't think Maple is the only platform that ever use PowerPC 970 processors(that is why this driver should depend on PP64, rather than PPC_MAPLE).

Thanks,

Harry

Hi Arnd,

I did try to get resource information from its DTB node first, the "hostbridge" node do can be found successfully, however, unfortunately, as I put in the notes in that function, the #address-cells and #size-cells specified by its parent node are both 2, but the cell number used in its "reg" property is actually 1, as

reg = <0xf8000000 0x1000000>;

which will make of_address_to_resource() failed with -EINVAL; that's why I have to set it up from scratch manually.

Cheers,

Harry




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