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
136

source code of linux/drivers/scsi/arm/acornscsi-io.S