1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 *  linux/drivers/acorn/scsi/acornscsi-io.S: Acorn SCSI card IO
  4 */
  5#include <linux/linkage.h>
  6
  7#include <asm/assembler.h>
  8#include <mach/hardware.h>
  9
 10#if defined(__APCS_32__)
 11#define LOADREGS(t,r,l...)	ldm##t	r, l
 12#elif defined(__APCS_26__)
 13#define LOADREGS(t,r,l...)	ldm##t	r, l##^
 14#endif
 15
 16@ Purpose: transfer a block of data from the acorn scsi card to memory
 17@ Proto  : void acornscsi_in(unsigned int addr_start, char *buffer, int length)
 18@ Returns: nothing
 19
 20		.align
 21ENTRY(__acornscsi_in)
 22		stmfd	sp!, {r4 - r7, lr}
 23		bic	r0, r0, #3
 24		mov	lr, #0xff
 25		orr	lr, lr, #0xff00
 26acornscsi_in16lp:
 27		subs	r2, r2, #16
 28		bmi	acornscsi_in8
 29		ldmia	r0!, {r3, r4, r5, r6}
 30		and	r3, r3, lr
 31		orr	r3, r3, r4, lsl #16
 32		and 	r4, r5, lr
 33		orr	r4, r4, r6, lsl #16
 34		ldmia	r0!, {r5, r6, r7, ip}
 35		and	r5, r5, lr
 36		orr	r5, r5, r6, lsl #16
 37		and	r6, r7, lr
 38		orr	r6, r6, ip, lsl #16
 39		stmia	r1!, {r3 - r6}
 40		bne	acornscsi_in16lp
 41		LOADREGS(fd, sp!, {r4 - r7, pc})
 42
 43acornscsi_in8:	adds	r2, r2, #8
 44		bmi	acornscsi_in4
 45		ldmia	r0!, {r3, r4, r5, r6}
 46		and	r3, r3, lr
 47		orr	r3, r3, r4, lsl #16
 48		and	r4, r5, lr
 49		orr	r4, r4, r6, lsl #16
 50		stmia	r1!, {r3 - r4}
 51		LOADREGS(eqfd, sp!, {r4 - r7, pc})
 52		sub	r2, r2, #8
 53
 54acornscsi_in4:	adds	r2, r2, #4
 55		bmi	acornscsi_in2
 56		ldmia	r0!, {r3, r4}
 57		and	r3, r3, lr
 58		orr	r3, r3, r4, lsl #16
 59		str	r3, [r1], #4
 60		LOADREGS(eqfd, sp!, {r4 - r7, pc})
 61		sub	r2, r2, #4
 62
 63acornscsi_in2:	adds	r2, r2, #2
 64		ldr	r3, [r0], #4
 65		and	r3, r3, lr
 66		strb	r3, [r1], #1
 67		mov	r3, r3, lsr #8
 68		strplb	r3, [r1], #1
 69		LOADREGS(fd, sp!, {r4 - r7, pc})
 70
 71@ Purpose: transfer a block of data from memory to the acorn scsi card
 72@ Proto  : void acornscsi_in(unsigned int addr_start, char *buffer, int length)
 73@ Returns: nothing
 74
 75ENTRY(__acornscsi_out)
 76		stmfd	sp!, {r4 - r6, lr}
 77		bic	r0, r0, #3
 78acornscsi_out16lp:
 79		subs	r2, r2, #16
 80		bmi	acornscsi_out8
 81		ldmia	r1!, {r4, r6, ip, lr}
 82		mov	r3, r4, lsl #16
 83		orr	r3, r3, r3, lsr #16
 84		mov	r4, r4, lsr #16
 85		orr	r4, r4, r4, lsl #16
 86		mov	r5, r6, lsl #16
 87		orr	r5, r5, r5, lsr #16
 88		mov	r6, r6, lsr #16
 89		orr	r6, r6, r6, lsl #16
 90		stmia	r0!, {r3, r4, r5, r6}
 91		mov	r3, ip, lsl #16
 92		orr	r3, r3, r3, lsr #16
 93		mov	r4, ip, lsr #16
 94		orr	r4, r4, r4, lsl #16
 95		mov	ip, lr, lsl #16
 96		orr	ip, ip, ip, lsr #16
 97		mov	lr, lr, lsr #16
 98		orr	lr, lr, lr, lsl #16
 99		stmia	r0!, {r3, r4, ip, lr}
100		bne	acornscsi_out16lp
101		LOADREGS(fd, sp!, {r4 - r6, pc})
102
103acornscsi_out8:	adds	r2, r2, #8
104		bmi	acornscsi_out4
105		ldmia	r1!, {r4, r6}
106		mov	r3, r4, lsl #16
107		orr	r3, r3, r3, lsr #16
108		mov	r4, r4, lsr #16
109		orr	r4, r4, r4, lsl #16
110		mov	r5, r6, lsl #16
111		orr	r5, r5, r5, lsr #16
112		mov	r6, r6, lsr #16
113		orr	r6, r6, r6, lsl #16
114		stmia	r0!, {r3, r4, r5, r6}
115		LOADREGS(eqfd, sp!, {r4 - r6, pc})
116
117		sub	r2, r2, #8
118acornscsi_out4:	adds	r2, r2, #4
119		bmi	acornscsi_out2
120		ldr	r4, [r1], #4
121		mov	r3, r4, lsl #16
122		orr	r3, r3, r3, lsr #16
123		mov	r4, r4, lsr #16
124		orr	r4, r4, r4, lsl #16
125		stmia	r0!, {r3, r4}
126		LOADREGS(eqfd, sp!, {r4 - r6, pc})
127
128		sub	r2, r2, #4
129acornscsi_out2:	adds	r2, r2, #2
130		ldr	r3, [r1], #2
131		strb	r3, [r0], #1
132		mov	r3, r3, lsr #8
133		strplb	r3, [r0], #1
134		LOADREGS(fd, sp!, {r4 - r6, pc})
135