1/*
2 *  linux/arch/arm/mach-omap1/ams-delta-fiq-handler.S
3 *
4 *  Based on  linux/arch/arm/lib/floppydma.S
5 *  Renamed and modified to work with 2.6 kernel by Matt Callow
6 *  Copyright (C) 1995, 1996 Russell King
7 *  Copyright (C) 2004 Pete Trapps
8 *  Copyright (C) 2006 Matt Callow
9 *  Copyright (C) 2010 Janusz Krzysztofik
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License version 2
13 * as published by the Free Software Foundation.
14 */
15
16#include <linux/linkage.h>
17#include <linux/platform_data/ams-delta-fiq.h>
18#include <linux/platform_data/gpio-omap.h>
19
20#include <asm/assembler.h>
21
22#include "ams-delta-fiq.h"
23#include "board-ams-delta.h"
24#include "iomap.h"
25#include "soc.h"
26
27/*
28 * OMAP1510 GPIO related symbol copied from arch/arm/mach-omap1/gpio15xx.c.
29 * Unfortunately, it was not placed in a separate header file.
30 */
31#define OMAP1510_GPIO_BASE		0xFFFCE000
32
33/* GPIO register bitmasks */
34#define KEYBRD_DATA_MASK		(0x1 << AMS_DELTA_GPIO_PIN_KEYBRD_DATA)
35#define KEYBRD_CLK_MASK			(0x1 << AMS_DELTA_GPIO_PIN_KEYBRD_CLK)
36#define MODEM_IRQ_MASK			(0x1 << AMS_DELTA_GPIO_PIN_MODEM_IRQ)
37#define HOOK_SWITCH_MASK		(0x1 << AMS_DELTA_GPIO_PIN_HOOK_SWITCH)
38#define OTHERS_MASK			(MODEM_IRQ_MASK | HOOK_SWITCH_MASK)
39
40/* IRQ handler register bitmasks */
41#define DEFERRED_FIQ_MASK		OMAP_IRQ_BIT(INT_DEFERRED_FIQ)
42#define GPIO_BANK1_MASK  		OMAP_IRQ_BIT(INT_GPIO_BANK1)
43
44/* Driver buffer byte offsets */
45#define BUF_MASK			(FIQ_MASK * 4)
46#define BUF_STATE			(FIQ_STATE * 4)
47#define BUF_KEYS_CNT			(FIQ_KEYS_CNT * 4)
48#define BUF_TAIL_OFFSET			(FIQ_TAIL_OFFSET * 4)
49#define BUF_HEAD_OFFSET			(FIQ_HEAD_OFFSET * 4)
50#define BUF_BUF_LEN			(FIQ_BUF_LEN * 4)
51#define BUF_KEY				(FIQ_KEY * 4)
52#define BUF_MISSED_KEYS			(FIQ_MISSED_KEYS * 4)
53#define BUF_BUFFER_START		(FIQ_BUFFER_START * 4)
54#define BUF_GPIO_INT_MASK		(FIQ_GPIO_INT_MASK * 4)
55#define BUF_KEYS_HICNT			(FIQ_KEYS_HICNT * 4)
56#define BUF_IRQ_PEND			(FIQ_IRQ_PEND * 4)
57#define BUF_SIR_CODE_L1			(FIQ_SIR_CODE_L1 * 4)
58#define BUF_SIR_CODE_L2			(IRQ_SIR_CODE_L2 * 4)
59#define BUF_CNT_INT_00			(FIQ_CNT_INT_00 * 4)
60#define BUF_CNT_INT_KEY			(FIQ_CNT_INT_KEY * 4)
61#define BUF_CNT_INT_MDM			(FIQ_CNT_INT_MDM * 4)
62#define BUF_CNT_INT_03			(FIQ_CNT_INT_03 * 4)
63#define BUF_CNT_INT_HSW			(FIQ_CNT_INT_HSW * 4)
64#define BUF_CNT_INT_05			(FIQ_CNT_INT_05 * 4)
65#define BUF_CNT_INT_06			(FIQ_CNT_INT_06 * 4)
66#define BUF_CNT_INT_07			(FIQ_CNT_INT_07 * 4)
67#define BUF_CNT_INT_08			(FIQ_CNT_INT_08 * 4)
68#define BUF_CNT_INT_09			(FIQ_CNT_INT_09 * 4)
69#define BUF_CNT_INT_10			(FIQ_CNT_INT_10 * 4)
70#define BUF_CNT_INT_11			(FIQ_CNT_INT_11 * 4)
71#define BUF_CNT_INT_12			(FIQ_CNT_INT_12 * 4)
72#define BUF_CNT_INT_13			(FIQ_CNT_INT_13 * 4)
73#define BUF_CNT_INT_14			(FIQ_CNT_INT_14 * 4)
74#define BUF_CNT_INT_15			(FIQ_CNT_INT_15 * 4)
75#define BUF_CIRC_BUFF			(FIQ_CIRC_BUFF * 4)
76
77
78/*
79 * Register usage
80 * r8  - temporary
81 * r9  - the driver buffer
82 * r10 - temporary
83 * r11 - interrupts mask
84 * r12 - base pointers
85 * r13 - interrupts status
86 */
87
88	.text
89
90	.global qwerty_fiqin_end
91
92ENTRY(qwerty_fiqin_start)
93	@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
94	@ FIQ intrrupt handler
95	ldr r12, omap_ih1_base			@ set pointer to level1 handler
96
97	ldr r11, [r12, #IRQ_MIR_REG_OFFSET]	@ fetch interrupts mask
98
99	ldr r13, [r12, #IRQ_ITR_REG_OFFSET]	@ fetch interrupts status
100	bics r13, r13, r11			@ clear masked - any left?
101	beq exit				@ none - spurious FIQ? exit
102
103	ldr r10, [r12, #IRQ_SIR_FIQ_REG_OFFSET]	@ get requested interrupt number
104
105	mov r8, #2				@ reset FIQ agreement
106	str r8, [r12, #IRQ_CONTROL_REG_OFFSET]
107
108	cmp r10, #(INT_GPIO_BANK1 - NR_IRQS_LEGACY)	@ is it GPIO interrupt?
109	beq gpio				@ yes - process it
110
111	mov r8, #1
112	orr r8, r11, r8, lsl r10		@ mask spurious interrupt
113	str r8, [r12, #IRQ_MIR_REG_OFFSET]
114exit:
115	subs	pc, lr, #4			@ return from FIQ
116	@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
117
118
119	@@@@@@@@@@@@@@@@@@@@@@@@@@@
120gpio:	@ GPIO bank interrupt handler
121	ldr r12, omap1510_gpio_base		@ set base pointer to GPIO bank
122
123	ldr r11, [r12, #OMAP1510_GPIO_INT_MASK]	@ fetch GPIO interrupts mask
124restart:
125	ldr r13, [r12, #OMAP1510_GPIO_INT_STATUS]	@ fetch status bits
126	bics r13, r13, r11			@ clear masked - any left?
127	beq exit				@ no - spurious interrupt? exit
128
129	orr r11, r11, r13			@ mask all requested interrupts
130	str r11, [r12, #OMAP1510_GPIO_INT_MASK]
131
132	ands r10, r13, #KEYBRD_CLK_MASK		@ extract keyboard status - set?
133	beq hksw				@ no - try next source
134
135
136	@@@@@@@@@@@@@@@@@@@@@@
137	@ Keyboard clock FIQ mode interrupt handler
138	@ r10 now contains KEYBRD_CLK_MASK, use it
139	str r10, [r12, #OMAP1510_GPIO_INT_STATUS]	@ ack the interrupt
140	bic r11, r11, r10				@ unmask it
141	str r11, [r12, #OMAP1510_GPIO_INT_MASK]
142
143	@ Process keyboard data
144	ldr r8, [r12, #OMAP1510_GPIO_DATA_INPUT]	@ fetch GPIO input
145
146	ldr r10, [r9, #BUF_STATE]		@ fetch kbd interface state
147	cmp r10, #0				@ are we expecting start bit?
148	bne data				@ no - go to data processing
149
150	ands r8, r8, #KEYBRD_DATA_MASK		@ check start bit - detected?
151	beq hksw				@ no - try next source
152
153	@ r8 contains KEYBRD_DATA_MASK, use it
154	str r8, [r9, #BUF_STATE]		@ enter data processing state
155	@ r10 already contains 0, reuse it
156	str r10, [r9, #BUF_KEY]			@ clear keycode
157	mov r10, #2				@ reset input bit mask
158	str r10, [r9, #BUF_MASK]
159
160	@ Mask other GPIO line interrupts till key done
161	str r11, [r9, #BUF_GPIO_INT_MASK]	@ save mask for later restore
162	mvn r11, #KEYBRD_CLK_MASK		@ prepare all except kbd mask
163	str r11, [r12, #OMAP1510_GPIO_INT_MASK]	@ store into the mask register
164
165	b restart				@ restart
166
167data:	ldr r10, [r9, #BUF_MASK]		@ fetch current input bit mask
168
169	@ r8 still contains GPIO input bits
170	ands r8, r8, #KEYBRD_DATA_MASK		@ is keyboard data line low?
171	ldreq r8, [r9, #BUF_KEY]		@ yes - fetch collected so far,
172	orreq r8, r8, r10			@ set 1 at current mask position
173	streq r8, [r9, #BUF_KEY]		@ and save back
174
175	mov r10, r10, lsl #1			@ shift mask left
176	bics r10, r10, #0x800			@ have we got all the bits?
177	strne r10, [r9, #BUF_MASK]		@ not yet - store the mask
178	bne restart				@ and restart
179
180	@ r10 already contains 0, reuse it
181	str r10, [r9, #BUF_STATE]		@ reset state to start
182
183	@ Key done - restore interrupt mask
184	ldr r10, [r9, #BUF_GPIO_INT_MASK]	@ fetch saved mask
185	and r11, r11, r10			@ unmask all saved as unmasked
186	str r11, [r12, #OMAP1510_GPIO_INT_MASK]	@ restore into the mask register
187
188	@ Try appending the keycode to the circular buffer
189	ldr r10, [r9, #BUF_KEYS_CNT]		@ get saved keystrokes count
190	ldr r8, [r9, #BUF_BUF_LEN]		@ get buffer size
191	cmp r10, r8				@ is buffer full?
192	beq hksw				@ yes - key lost, next source
193
194	add r10, r10, #1			@ incremet keystrokes counter
195	str r10, [r9, #BUF_KEYS_CNT]
196
197	ldr r10, [r9, #BUF_TAIL_OFFSET]		@ get buffer tail offset
198	@ r8 already contains buffer size
199	cmp r10, r8				@ end of buffer?
200	moveq r10, #0				@ yes - rewind to buffer start
201
202	ldr r12, [r9, #BUF_BUFFER_START]	@ get buffer start address
203	add r12, r12, r10, LSL #2		@ calculate buffer tail address
204	ldr r8, [r9, #BUF_KEY]			@ get last keycode
205	str r8, [r12]				@ append it to the buffer tail
206
207	add r10, r10, #1			@ increment buffer tail offset
208	str r10, [r9, #BUF_TAIL_OFFSET]
209
210	ldr r10, [r9, #BUF_CNT_INT_KEY]		@ increment interrupts counter
211	add r10, r10, #1
212	str r10, [r9, #BUF_CNT_INT_KEY]
213	@@@@@@@@@@@@@@@@@@@@@@@@
214
215
216hksw:	@Is hook switch interrupt requested?
217	tst r13, #HOOK_SWITCH_MASK 		@ is hook switch status bit set?
218	beq mdm					@ no - try next source
219
220
221	@@@@@@@@@@@@@@@@@@@@@@@@
222	@ Hook switch interrupt FIQ mode simple handler
223
224	@ Don't toggle active edge, the switch always bounces
225
226	@ Increment hook switch interrupt counter
227	ldr r10, [r9, #BUF_CNT_INT_HSW]
228	add r10, r10, #1
229	str r10, [r9, #BUF_CNT_INT_HSW]
230	@@@@@@@@@@@@@@@@@@@@@@@@
231
232
233mdm:	@Is it a modem interrupt?
234	tst r13, #MODEM_IRQ_MASK 		@ is modem status bit set?
235	beq irq					@ no - check for next interrupt
236
237
238	@@@@@@@@@@@@@@@@@@@@@@@@
239	@ Modem FIQ mode interrupt handler stub
240
241	@ Increment modem interrupt counter
242	ldr r10, [r9, #BUF_CNT_INT_MDM]
243	add r10, r10, #1
244	str r10, [r9, #BUF_CNT_INT_MDM]
245	@@@@@@@@@@@@@@@@@@@@@@@@
246
247
248irq:	@ Place deferred_fiq interrupt request
249	ldr r12, deferred_fiq_ih_base		@ set pointer to IRQ handler
250	mov r10, #DEFERRED_FIQ_MASK		@ set deferred_fiq bit
251	str r10, [r12, #IRQ_ISR_REG_OFFSET] 	@ place it in the ISR register
252
253	ldr r12, omap1510_gpio_base		@ set pointer back to GPIO bank
254	b restart				@ check for next GPIO interrupt
255	@@@@@@@@@@@@@@@@@@@@@@@@@@@
256
257
258/*
259 * Virtual addresses for IO
260 */
261omap_ih1_base:
262	.word OMAP1_IO_ADDRESS(OMAP_IH1_BASE)
263deferred_fiq_ih_base:
264	.word OMAP1_IO_ADDRESS(DEFERRED_FIQ_IH_BASE)
265omap1510_gpio_base:
266	.word OMAP1_IO_ADDRESS(OMAP1510_GPIO_BASE)
267qwerty_fiqin_end:
268
269/*
270 * Check the size of the FIQ,
271 * it cannot go beyond 0xffff0200, and is copied to 0xffff001c
272 */
273.if (qwerty_fiqin_end - qwerty_fiqin_start) > (0x200 - 0x1c)
274	.err
275.endif
276