On Sat, 2015-08-29 at 09:33 +0300, Siarhei Siamashka wrote:
> Add a new field 'spl_addr' to the SoC description structure and adjust
> the code to honor it. This is needed for supporting Allwinner A80.
>
> Tested on Allwinner A20 by changing the 'spl_addr' to 0x28000 in the
> 'fel' tool and using a custom build of U-Boot (CONFIG_SPL_TEXT_BASE
> changed from 0x20 to 0x28020).
>
> Signed-off-by: Siarhei Siamashka <[email protected]>
> ---
> fel-to-spl-thunk.S | 22 ++++++--------
> fel-to-spl-thunk.h | 89
> ++++++++++++++++++++++++++----------------------------
> fel.c | 29 ++++++++++--------
> 3 files changed, 70 insertions(+), 70 deletions(-)
>
> diff --git a/fel-to-spl-thunk.S b/fel-to-spl-thunk.S
> index fb5dfde..e3fa6f2 100644
> --- a/fel-to-spl-thunk.S
> +++ b/fel-to-spl-thunk.S
> @@ -69,6 +69,7 @@ SWAPTBL> > > .req> > r4
> FULLSIZE> > .req> > r5
> BUFSIZE> > > .req> > r6
> CHECKSUM> > .req> > r7
> +SPL_ADDR> > .req> > r8
>
> entry_point:
> > > b> > setup_stack
> @@ -87,7 +88,7 @@ stack_end:
>
> > > /* A function, which walks the table and swaps all buffers */
> swap_all_buffers:
> -> > adr> > SWAPTBL, swaptbl_start
> +> > adr> > SWAPTBL, appended_data + 4
> swap_next_buffer:
> > > ldr> > BUF1, [SWAPTBL], #4
> > > ldr> > BUF2, [SWAPTBL], #4
> @@ -104,6 +105,7 @@ swap_next_word:
> > > b> > swap_next_buffer
>
> setup_stack: /* Save the original SP, LR and CPSR to stack */
> +> > ldr> > SPL_ADDR, appended_data
> > > adr> > BUF1, stack_end
> > > str> > sp, [BUF1, #-4]!
> > > mov> > sp, BUF1
> @@ -125,7 +127,7 @@ setup_stack: /* Save the original SP, LR and CPSR to
> stack */
> verify_checksum:
> > > movw> > CHECKSUM, #0x6c39
> > > movt> > CHECKSUM, #0x5f0a
> -> > mov> > BUF1, #0
> +> > mov> > BUF1, SPL_ADDR
> > > ldr FULLSIZE, [BUF1, #16]
> check_next_word:
> > > ldr> > TMP1, [BUF1], #4
> @@ -133,39 +135,35 @@ check_next_word:
> > > add> > CHECKSUM, CHECKSUM, TMP1
> > > bne> > check_next_word
>
> -> > mov> > BUF1, #0
> -> > ldr> > TMP1, [BUF1, #12]
> +> > ldr> > TMP1, [SPL_ADDR, #12]
> > > subs> > CHECKSUM, CHECKSUM, TMP1, lsl #1
> > > bne> > checksum_is_bad
>
> > > /* Change 'eGON.BT0' -> 'eGON.FEL' */
> -> > mov> > BUF1, #0
> > > movw> > TMP1, (('F' << 8) + '.')
> > > movt> > TMP1, (('L' << 8) + 'E')
> -> > str> > TMP1, [BUF1, #8]
> +> > str> > TMP1, [SPL_ADDR, #8]
>
> > > /* Call the SPL code */
> > > dsb
> > > isb
> -> > blx> > BUF1
> +> > blx> > SPL_ADDR
>
> > > /* Return back to FEL */
> > > b> > return_to_fel
>
> cache_is_unsupported:
> > > /* Bail out if cache is enabled and change 'eGON.BT0' -> 'eGON.???' */
> -> > mov> > BUF1, #0
> > > movw> > TMP1, (('?' << 8) + '.')
> > > movt> > TMP1, (('?' << 8) + '?')
> -> > str> > TMP1, [BUF1, #8]
> +> > str> > TMP1, [SPL_ADDR, #8]
> > > b> > return_to_fel_noswap
>
> checksum_is_bad:
> > > /* The checksum test failed, so change 'eGON.BT0' -> 'eGON.BAD' */
> -> > mov> > BUF1, #0
> > > movw> > TMP1, (('B' << 8) + '.')
> > > movt> > TMP1, (('D' << 8) + 'A')
> -> > str> > TMP1, [BUF1, #8]
> +> > str> > TMP1, [SPL_ADDR, #8]
>
> return_to_fel:
> > > bl> > swap_all_buffers
> @@ -175,4 +173,4 @@ return_to_fel_noswap:
> > > ldr sp, [sp]
> > > bx> > lr
>
> -swaptbl_start:
> +appended_data:
If I'm reading correctly you've changed things so that there is an
implicit data structure present here, namely the spl addr followed by
the swaptbl (as before).
I think this would be clearer if it were explicit, can you do:
spl_addr:
.word 0 /* Filled in by fel tool */
swaptbl_start:
or does something prevent this? I suppose it would make the thunk
appear larger are require accessing from C with END-N rather than
END+N, which might be undesirable.
If it isn't possible/desirable maybe just a comment describing what
should live here and/or some #define's for the offsets would be useful?
Doing asm-offset.S style tricks to let the C and ASM code use a shared
data structure is probably overkill at this point, but might be worth
considering if this grows more fields.
Ian.
--
You received this message because you are subscribed to the Google Groups
"linux-sunxi" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
For more options, visit https://groups.google.com/d/optout.
