diff options
Diffstat (limited to 'drivers/acorn/block/mfm.S')
| -rw-r--r-- | drivers/acorn/block/mfm.S | 162 |
1 files changed, 0 insertions, 162 deletions
diff --git a/drivers/acorn/block/mfm.S b/drivers/acorn/block/mfm.S deleted file mode 100644 index c90cbd41ce21..000000000000 --- a/drivers/acorn/block/mfm.S +++ /dev/null @@ -1,162 +0,0 @@ -@ Read/Write DMA code for the ST506/MFM hard drive controllers on the A400 Acorn Archimedes -@ motherboard and on ST506 expansion podules. -@ (c) David Alan Gilbert (linux@treblig.org) 1996-1999 - -#include <asm/assembler.h> - -hdc63463_irqdata: -@ Controller base address - .global hdc63463_baseaddress -hdc63463_baseaddress: - .word 0 - - .global hdc63463_irqpolladdress -hdc63463_irqpolladdress: - .word 0 - - .global hdc63463_irqpollmask -hdc63463_irqpollmask: - .word 0 - -@ where to read/write data from the kernel data space - .global hdc63463_dataptr -hdc63463_dataptr: - .word 0 - -@ Number of bytes left to transfer - .global hdc63463_dataleft -hdc63463_dataleft: - .word 0 - -@ ------------------------------------------------------------------------- -@ hdc63463_writedma: DMA from host to controller -@ internal reg usage: r0=hdc base address, r1=irq poll address, r2=poll mask -@ r3=data ptr, r4=data left, r5,r6=temporary - .global hdc63463_writedma -hdc63463_writedma: - stmfd sp!,{r4-r7} - adr r5,hdc63463_irqdata - ldmia r5,{r0,r1,r2,r3,r4} - -writedma_again: - - @ test number of remaining bytes to transfer - cmp r4,#0 - beq writedma_end - bmi writedma_end - - @ Check the hdc is interrupting - ldrb r5,[r1,#0] - tst r5,r2 - beq writedma_end - - @ Transfer a block of upto 256 bytes - cmp r4,#256 - movlt r7,r4 - movge r7,#256 - - @ Check the hdc is still busy and command has not ended and no errors - ldr r5,[r0,#32] @ Status reg - 16 bit - its the top few bits which are status - @ think we should continue DMA until it drops busy - perhaps this was - @ the main problem with corrected errors causing a hang - @tst r5,#0x3c00 @ Test for things which should be off - @bne writedma_end - and r5,r5,#0x8000 @ This is test for things which should be on: Busy - cmp r5,#0x8000 - bne writedma_end - - @ Bytes remaining at end - sub r4,r4,r7 - - @ HDC Write register location - add r0,r0,#32+8 - -writedma_loop: - @ OK - pretty sure we should be doing this - - ldr r5,[r3],#4 @ Get a word to be written - @ get bottom half to be sent first - mov r6,r5,lsl#16 @ Separate the first 2 bytes - orr r2,r6,r6,lsr #16 @ Duplicate them in the bottom half of the word - @ now the top half - mov r6,r5,lsr#16 @ Get 2nd 2 bytes - orr r6,r6,r6,lsl#16 @ Duplicate - @str r6,[r0] @ to hdc - stmia r0,{r2,r6} - subs r7,r7,#4 @ Dec. number of bytes left - bne writedma_loop - - @ If we were too slow we had better go through again - DAG - took out with new interrupt routine - @ sub r0,r0,#32+8 - @ adr r2,hdc63463_irqdata - @ ldr r2,[r2,#8] - @ b writedma_again - -writedma_end: - adr r5,hdc63463_irqdata+12 - stmia r5,{r3,r4} - ldmfd sp!,{r4-r7} - RETINSTR(mov,pc,lr) - -@ ------------------------------------------------------------------------- -@ hdc63463_readdma: DMA from controller to host -@ internal reg usage: r0=hdc base address, r1=irq poll address, r2=poll mask -@ r3=data ptr, r4=data left, r5,r6=temporary - .global hdc63463_readdma -hdc63463_readdma: - stmfd sp!,{r4-r7} - adr r5,hdc63463_irqdata - ldmia r5,{r0,r1,r2,r3,r4} - -readdma_again: - @ test number of remaining bytes to transfer - cmp r4,#0 - beq readdma_end - bmi readdma_end - - @ Check the hdc is interrupting - ldrb r5,[r1,#0] - tst r5,r2 - beq readdma_end - - @ Check the hdc is still busy and command has not ended and no errors - ldr r5,[r0,#32] @ Status reg - 16 bit - its the top few bits which are status - @ think we should continue DMA until it drops busy - perhaps this was - @ the main problem with corrected errors causing a hang - @tst r5,#0x3c00 @ Test for things which should be off - @bne readdma_end - and r5,r5,#0x8000 @ This is test for things which should be on: Busy - cmp r5,#0x8000 - bne readdma_end - - @ Transfer a block of upto 256 bytes - cmp r4,#256 - movlt r7,r4 - movge r7,#256 - - @ Bytes remaining at end - sub r4,r4,r7 - - @ Set a pointer to the data register in the HDC - add r0,r0,#8 -readdma_loop: - @ OK - pretty sure we should be doing this - ldmia r0,{r5,r6} - mov r5,r5,lsl#16 - mov r6,r6,lsl#16 - orr r6,r6,r5,lsr #16 - str r6,[r3],#4 - subs r7,r7,#4 @ Decrement bytes to go - bne readdma_loop - - @ Try reading multiple blocks - if this was fast enough then I do not think - @ this should help - NO taken out DAG - new interrupt handler has - @ non-consecutive memory blocks - @ sub r0,r0,#8 - @ b readdma_again - -readdma_end: - adr r5,hdc63463_irqdata+12 - stmia r5,{r3,r4} - ldmfd sp!,{r4-r7} - RETINSTR(mov,pc,lr) |