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| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2018-06-04 00:21:34 +1000 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2018-06-04 00:21:34 +1000 |
| commit | ff62039f85b68f2b5329d3f3971fbe747e1e47b0 (patch) | |
| tree | 54f4f8957d234aea37e84b5ad059ee70c3d2f1c0 /cf-code/cf-fsi-fw.S | |
| parent | de2c276d1329777b95f7a1d6dec6a0f7b111a991 (diff) | |
| download | cf-fsi-ff62039f85b68f2b5329d3f3971fbe747e1e47b0.tar.gz cf-fsi-ff62039f85b68f2b5329d3f3971fbe747e1e47b0.zip | |
Cache clock GPIO bit number in a register
bset/bclk instructions are shorter when using a register,
this results in a small perf. improvement.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'cf-code/cf-fsi-fw.S')
| -rw-r--r-- | cf-code/cf-fsi-fw.S | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/cf-code/cf-fsi-fw.S b/cf-code/cf-fsi-fw.S index abfea09..32f6aa8 100644 --- a/cf-code/cf-fsi-fw.S +++ b/cf-code/cf-fsi-fw.S @@ -24,8 +24,8 @@ * A6 : CMD/RESP pointer * A7 : Stack pointer * D7 : clock GPIO cache (and data on Romulus) - * D6 : data GPIO cache (when need - * D5 : unused + * D6 : data GPIO cache (when needed) + * D5 : clock bit number * D4 : data value * D3 : loop counter * D2 : command register @@ -69,9 +69,9 @@ /* clock_toggle: toggle the clock down and back up */ .macro clock_toggle - bclr.l #CLOCK_GPIO_BIT,%DCLK /* clock low */ + bclr.l %d5,%DCLK /* clock low */ move.l %DCLK,%a5@(0) - bset.l #CLOCK_GPIO_BIT,%DCLK /* clock high */ + bset.l %d5,%DCLK /* clock high */ move.l %DCLK,%a5@(0) .endm @@ -110,11 +110,11 @@ * note: bit 0 of reg must already be cleared */ .macro clock_in_bit reg:req tmp:req tmp2:req - bclr.l #CLOCK_GPIO_BIT,%DCLK /* clock low */ + bclr.l %d5,%DCLK /* clock low */ move.l %DCLK,%a5@(0) move.l %a4@(0),\tmp /* dummy read */ move.l %a4@(0),\tmp /* actual read */ - bset.l #CLOCK_GPIO_BIT,%DCLK /* clock high */ + bset.l %d5,%DCLK /* clock high */ move.l %DCLK,%a5@(0) moveq.l #DATA_GPIO_BIT,\tmp2 lsr.l \tmp2,\tmp @@ -164,6 +164,9 @@ _start: add.l #DATA_GPIO_REG,%a4 movea.l #CVIC_BASE,%a2 + /* Store clock bit number */ + moveq.l #CLOCK_GPIO_BIT,%d5 + /* Load GPIO values into caches and Configure clock & data GPIO as output */ move.l %a5@(0),%DCLK move.l %a4@(0),%DDAT |
