[U-Boot] [PATCH] cmd: booti: fix the image runtime location

[Peng Fan <van.freenix@gmail.com>]

Hi Tom,

On Mon, Sep 12, 2016 at 08:04:01AM -0400, Tom Rini wrote:
>On Mon, Sep 12, 2016 at 05:18:53PM +0800, Peng Fan wrote:
>> On Mon, Sep 12, 2016 at 05:07:58PM +0800, Peng Fan wrote:
>> >We should not use "bi_dram[0].start + text_offset" as the image dst.
>> >The text_offset maybe 0 for some images, such as XEN. Then the dst
>> >is actually bi_dram[0].start, which maybe the location of spin table.
>> >
>> >Let's use "images->ep & ~(ih->text_offset)" as the dst address.
>> 
>> This patch maybe not that correct according to the doc from Linux kernel.
>> "
>> The Image must be placed text_offset bytes from a 2MB aligned base
>> address anywhere in usable system RAM and called there. The region
>> between the 2 MB aligned base address and the start of the image has no
>> special significance to the kernel, and may be used for other purposes.
>> "
>> 
>> Now I do not have a good idea that we may have a spin table in the start
>> of DRAM or even a small firmware.
>> 
>> Is it better to change gd->bd->bi_dram[0].start?
>> For example physical dram starts from 0x80000000, but 4K is reserved at the beginning.
>> So is it ok to change gd->bd->bi_dram[0].start to 0x80001000?
>
>So, to be more precise, with v4.5 the memory location restrictions were
>relaxed.  So we first need to update cmd/booti.c to know that res1 is
>now 'flags' and that we must check bit3 to determine where / how to
>align the image.  In the case of bit3 == 0 we must continue to do what
>we do today.  In the case of bit3 == 1, we have to decide what exactly
>to do.  My first thought is to see if images->ep is 2MB aligned and if
>so move to images->ep + ih->text_offset.  If not 2MB aligned, align that
>and then add ih->text_offset.
>
>Then any areas that need to be reserved in memory, wherever they are,
>can still be marked off as reserved in the DT.


How about the following patch?
If it is ok, I'll send out a formal one.

diff --git a/cmd/booti.c b/cmd/booti.c
index 6c1c998..efa8bc8 100644
--- a/cmd/booti.c
+++ b/cmd/booti.c
@@ -20,7 +20,7 @@ struct Image_header {
 	uint32_t	code1;		/* Executable code */
 	uint64_t	text_offset;	/* Image load offset, LE */
 	uint64_t	image_size;	/* Effective Image size, LE */
-	uint64_t	res1;		/* reserved */
+	uint64_t	flags;		/* Information flags, LE */
 	uint64_t	res2;		/* reserved */
 	uint64_t	res3;		/* reserved */
 	uint64_t	res4;		/* reserved */
@@ -29,6 +29,7 @@ struct Image_header {
 };
 
 #define LINUX_ARM64_IMAGE_MAGIC	0x644d5241
+#define LINUX_PHYSICAL_PLACEMENT (0x1 << 3)
 
 static int booti_setup(bootm_headers_t *images)
 {
@@ -54,7 +55,11 @@ static int booti_setup(bootm_headers_t *images)
 	 * If we are not@the correct run-time location, set the new
 	 * correct location and then move the image there.
 	 */
-	dst = gd->bd->bi_dram[0].start + le64_to_cpu(ih->text_offset);
+	dst = gd->bd->bi_dram[0].start;
+	if (le64_to_cpu(ih->flags) & LINUX_PHYSICAL_PLACEMENT)
+		dst = round_up(images->ep, SZ_2M);
+
+	dst += le64_to_cpu(ih->text_offset);
 
 	unmap_sysmem(ih);
 
Thanks,
Peng.
>
>-- 
>Tom