diff mbox

[U-Boot] nios2: zap dly_clks

Message ID 1441775391-12716-1-git-send-email-thomas@wytron.com.tw
State Accepted, archived
Delegated to: Thomas Chou
Headers show

Commit Message

Thomas Chou Sept. 9, 2015, 5:09 a.m. UTC 
The dly_clks() in start.S is no use after switching to
generic timer. Remove it.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
---
 arch/nios2/cpu/start.S | 33 ---------------------------------
 1 file changed, 33 deletions(-)

Comments

Marek Vasut Sept. 9, 2015, 12:04 p.m. UTC | #1 
On Wednesday, September 09, 2015 at 07:09:51 AM, Thomas Chou wrote:
> The dly_clks() in start.S is no use after switching to
> generic timer. Remove it.
> 
> Signed-off-by: Thomas Chou <thomas@wytron.com.tw>

Cool :)

Acked-by: Marek Vasut <marex@denx.de>

Best regards,
Marek Vasut
Thomas Chou Sept. 15, 2015, 8:55 a.m. UTC | #2 
On 09/09/2015 01:09 PM, Thomas Chou wrote:
> The dly_clks() in start.S is no use after switching to
> generic timer. Remove it.
>
> Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
> ---
>   arch/nios2/cpu/start.S | 33 ---------------------------------
>   1 file changed, 33 deletions(-)
>

Applied to u-boot-nios.
diff mbox

Patch

diff --git a/arch/nios2/cpu/start.S b/arch/nios2/cpu/start.S
index f80b4f3..e92f06e 100644
--- a/arch/nios2/cpu/start.S
+++ b/arch/nios2/cpu/start.S
@@ -175,39 +175,6 @@  relocate_code:
 	callr	r8
 	ret
 
-/*
- * dly_clks -- Nios2 (like Nios1) doesn't have a timebase in
- * the core. For simple delay loops, we do our best by counting
- * instruction cycles.
- *
- * Instruction performance varies based on the core. For cores
- * with icache and static/dynamic branch prediction (II/f, II/s):
- *
- *	Normal ALU (e.g. add, cmp, etc):	1 cycle
- *	Branch (correctly predicted, taken):	2 cycles
- *	Negative offset is predicted (II/s).
- *
- * For cores without icache and no branch prediction (II/e):
- *
- *	Normal ALU (e.g. add, cmp, etc):	6 cycles
- *	Branch (no prediction):			6 cycles
- *
- * For simplicity, if an instruction cache is implemented we
- * assume II/f or II/s. Otherwise, we use the II/e.
- *
- */
-	.globl dly_clks
-
-dly_clks:
-
-#if (CONFIG_SYS_ICACHE_SIZE > 0)
-	subi	r4, r4, 3		/* 3 clocks/loop	*/
-#else
-	subi	r4, r4, 12		/* 12 clocks/loop	*/
-#endif
-	bge	r4, r0, dly_clks
-	ret
-
 	.data
 	.globl	version_string