boot failure with __iounmap changes in v3.3

[jonsmirl at gmail.com]

On Mon, Mar 12, 2012 at 4:18 PM, Nicolas Pitre <nicolas.pitre at linaro.org> wrote:
> On Mon, 12 Mar 2012, jonsmirl at gmail.com wrote:
>
>> I'm working on getting out of tree support for the NXP LPC31xx
>> ARM926EJS based CPUs ready for submission. Everything was working fine
>> on v3.2 but I lost the ability to boot with v3.3. The boot failure is
>> very early in the boot process. I did a bisect and came up with:
>>
>> [6ee723a6570a897208b76ab3e9a495e9106b2f8c] ARM: simplify __iounmap()
>> when dealing with section based mapping
>>
>> I tried to revert it but there have been a bunch of edits in this
>> file. Not sure how to go about debugging this.
>
> The first thing to look for is any overlap in the virtual memory ranges
> used in your struct map_desc array.  No overlap is allowed anymore.

There appear to be overlaps. I'll have to study things for a while to
figure out how to eliminate them. This is from a three year old NXP
BSP. We have a product based on the CPU and want to use a more recent
kernel.

They've defined multiple large peripheral regions...

/* APB4 address range*/
#define IO_APB4_PHYS      (0x17000000)
#define IO_APB4_SIZE      (0x00001000)

	{
		.virtual	= io_p2v(IO_APB4_PHYS),
		.pfn		= __phys_to_pfn(IO_APB4_PHYS),
		.length		= IO_APB4_SIZE,
		.type		= MT_DEVICE
	},

and then declared various devices inside of them...

/* DMA registers address range*/
#define DMA_PHYS          (0x17000000)
#define IO_DMA_REG_PHYS  (DMA_PHYS)
#define IO_DMA_REG_SIZE  (0x0000800)

	{
		.virtual	= io_p2v(IO_DMA_REG_PHYS),
		.pfn		= __phys_to_pfn(IO_DMA_REG_PHYS),
		.length		= IO_DMA_REG_SIZE,
		.type		= MT_DEVICE
	},

>
> Then make sure those virtual addresses are between VMALLOC_START
> (typically 0xf0000000 or below depending on the armount of RAM your
> system has) and VMALLOC_END which is 0xff000000.
>
>
> Nicolas



-- 
Jon Smirl
jonsmirl at gmail.com