summaryrefslogtreecommitdiff
path: root/recipes/linux/linux-omap-2.6.27/musb-rxtx.patch
blob: 79089094af7dfa3c0cf8b1d1c50b92b57a564e12 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
MUSB: Workaround for simultaneous TX and RX usage

MUSB RTL V1.4 has a hardware issue which results in a DMA controller
hang when TX and RX DMA channels are simultaneously enabled. This
affects at least OMAP2430 and OMAP34XX.

Since RX transfers are in Mode 0 and anyway result in one DMA interrupt
per packet, we can use System DMA to unload the RX fifos. MUSB DMA can
be used for all TX channels as before.

Tested with full-duplex TX and RX transfers using g_ether. Runs for 24
hours without a hang. Without this patch, the hang occurs within minutes.

This issue was first reported by Jon Hunter on [1]

[1] http://marc.info/?l=linux-omap&m=119634480534453&w=2

Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
---
Patch based on the linux-omap tree. I believe the tabs-to-spaces issue
has been resolved now, but this is the first patch I'm sending out to the
list after that.

Suggestions welcome for removing the 2 #ifdefs below. One suggestion was to
use a module parameter to decide whether to use system dma or mentor dma.

Patch updated with a few ifdefs removed and one compilation break resolved.

 drivers/usb/musb/Kconfig     |    8 ++
 drivers/usb/musb/musbhsdma.c |  163 +++++++++++++++++++++++++++++++++++--------
 2 files changed, 142 insertions(+), 29 deletions(-)

Index: linux-omap-2.6/drivers/usb/musb/musbhsdma.c
===================================================================
--- linux-omap-2.6.orig/drivers/usb/musb/musbhsdma.c	2008-07-28 10:54:37.000000000 +0530
+++ linux-omap-2.6/drivers/usb/musb/musbhsdma.c	2008-08-13 11:58:26.272902373 +0530
@@ -34,6 +34,7 @@
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include "musb_core.h"
+#include <mach/dma.h>
 
 #if defined(CONFIG_ARCH_OMAP2430) || defined(CONFIG_ARCH_OMAP3430)
 #include "omap2430.h"
@@ -64,6 +65,9 @@
 
 #define MUSB_HSDMA_CHANNELS		8
 
+#define MUSB_FIFO_ADDRESS(epnum)	\
+	((unsigned long) (OMAP_HSOTG_BASE + MUSB_FIFO_OFFSET(epnum)))
+
 struct musb_dma_controller;
 
 struct musb_dma_channel {
@@ -75,6 +79,8 @@ struct musb_dma_channel {
 	u8				bIndex;
 	u8				epnum;
 	u8				transmit;
+
+	int				sysdma_channel;
 };
 
 struct musb_dma_controller {
@@ -93,6 +99,42 @@ static int dma_controller_start(struct d
 	return 0;
 }
 
+#ifdef CONFIG_MUSB_USE_SYSTEM_DMA_RX
+static void musb_sysdma_completion(int lch, u16 ch_status, void *data)
+{
+	u32 dwAddress;
+	unsigned long flags;
+
+	struct dma_channel *pChannel;
+
+	struct musb_dma_channel *pImplChannel =
+					(struct musb_dma_channel *) data;
+	struct musb_dma_controller *controller = pImplChannel->controller;
+	struct musb *musb = controller->pDmaPrivate;
+	pChannel = &pImplChannel->Channel;
+
+	DBG(2, "lch = 0x%d, ch_status = 0x%x\n", lch, ch_status);
+	spin_lock_irqsave(&musb->lock, flags);
+
+	dwAddress = (u32) omap_get_dma_dst_pos(pImplChannel->sysdma_channel);
+	pChannel->actual_len = dwAddress - pImplChannel->dwStartAddress;
+
+	DBG(2, "ch %p, 0x%x -> 0x%x (%d / %d) %s\n",
+		pChannel, pImplChannel->dwStartAddress, dwAddress,
+		pChannel->actual_len, pImplChannel->len,
+		(pChannel->actual_len < pImplChannel->len) ?
+		"=> reconfig 0": "=> complete");
+
+	pChannel->status = MUSB_DMA_STATUS_FREE;
+	musb_dma_completion(musb, pImplChannel->epnum, pImplChannel->transmit);
+
+	spin_unlock_irqrestore(&musb->lock, flags);
+	return;
+}
+#else
+#define musb_sysdma_completion NULL
+#endif
+
 static void dma_channel_release(struct dma_channel *pChannel);
 
 static int dma_controller_stop(struct dma_controller *c)
@@ -144,6 +186,29 @@ static struct dma_channel *dma_channel_a
 			/* Tx => mode 1; Rx => mode 0 */
 			pChannel->desired_mode = transmit;
 			pChannel->actual_len = 0;
+			pImplChannel->sysdma_channel = -1;
+
+#ifdef CONFIG_MUSB_USE_SYSTEM_DMA_RX
+			if (!transmit) {
+				int ret;
+				ret = omap_request_dma(OMAP24XX_DMA_NO_DEVICE,
+					"MUSB SysDMA", musb_sysdma_completion,
+					(void *) pImplChannel,
+					&(pImplChannel->sysdma_channel));
+
+				if (ret) {
+					printk(KERN_ERR "request_dma failed:"
+							" %d\n", ret);
+					controller->bmUsedChannels &=
+								~(1 << bBit);
+					pChannel->status =
+							MUSB_DMA_STATUS_UNKNOWN;
+					pImplChannel->sysdma_channel = -1;
+					pChannel = NULL;
+				}
+			}
+#endif
+
 			break;
 		}
 	}
@@ -163,6 +228,12 @@ static void dma_channel_release(struct d
 		~(1 << pImplChannel->bIndex);
 
 	pChannel->status = MUSB_DMA_STATUS_UNKNOWN;
+
+	if (pImplChannel->sysdma_channel != -1) {
+		omap_stop_dma(pImplChannel->sysdma_channel);
+		omap_free_dma(pImplChannel->sysdma_channel);
+		pImplChannel->sysdma_channel = -1;
+	}
 }
 
 static void configure_channel(struct dma_channel *pChannel,
@@ -179,41 +250,69 @@ static void configure_channel(struct dma
 	DBG(4, "%p, pkt_sz %d, addr 0x%x, len %d, mode %d\n",
 			pChannel, packet_sz, dma_addr, len, mode);
 
-	if (mode) {
-		csr |= 1 << MUSB_HSDMA_MODE1_SHIFT;
-		BUG_ON(len < packet_sz);
+	if (pImplChannel->sysdma_channel != -1) {
+	/* System DMA */
+	/* RX: set src = FIFO */
+
+		omap_set_dma_transfer_params(pImplChannel->sysdma_channel,
+					OMAP_DMA_DATA_TYPE_S8,
+					len, 1, /* One frame */
+					OMAP_DMA_SYNC_ELEMENT,
+					OMAP24XX_DMA_NO_DEVICE,
+					0); /* Src Sync */
+
+		omap_set_dma_src_params(pImplChannel->sysdma_channel, 0,
+					OMAP_DMA_AMODE_CONSTANT,
+					MUSB_FIFO_ADDRESS(pImplChannel->epnum),
+					0, 0);
+
+		omap_set_dma_dest_params(pImplChannel->sysdma_channel, 0,
+					OMAP_DMA_AMODE_POST_INC, dma_addr,
+					0, 0);
+
+		omap_set_dma_dest_data_pack(pImplChannel->sysdma_channel, 1);
+		omap_set_dma_dest_burst_mode(pImplChannel->sysdma_channel,
+					OMAP_DMA_DATA_BURST_16);
+
+		omap_start_dma(pImplChannel->sysdma_channel);
+
+	} else { /* Mentor DMA */
+		if (mode) {
+			csr |= 1 << MUSB_HSDMA_MODE1_SHIFT;
+			BUG_ON(len < packet_sz);
 
-		if (packet_sz >= 64) {
-			csr |= MUSB_HSDMA_BURSTMODE_INCR16
+			if (packet_sz >= 64) {
+				csr |= MUSB_HSDMA_BURSTMODE_INCR16
 					<< MUSB_HSDMA_BURSTMODE_SHIFT;
-		} else if (packet_sz >= 32) {
-			csr |= MUSB_HSDMA_BURSTMODE_INCR8
+			} else if (packet_sz >= 32) {
+				csr |= MUSB_HSDMA_BURSTMODE_INCR8
 					<< MUSB_HSDMA_BURSTMODE_SHIFT;
-		} else if (packet_sz >= 16) {
-			csr |= MUSB_HSDMA_BURSTMODE_INCR4
+			} else if (packet_sz >= 16) {
+				csr |= MUSB_HSDMA_BURSTMODE_INCR4
 					<< MUSB_HSDMA_BURSTMODE_SHIFT;
+			}
 		}
-	}
 
-	csr |= (pImplChannel->epnum << MUSB_HSDMA_ENDPOINT_SHIFT)
-		| (1 << MUSB_HSDMA_ENABLE_SHIFT)
-		| (1 << MUSB_HSDMA_IRQENABLE_SHIFT)
-		| (pImplChannel->transmit
-				? (1 << MUSB_HSDMA_TRANSMIT_SHIFT)
-				: 0);
-
-	/* address/count */
-	musb_writel(mbase,
-		MUSB_HSDMA_CHANNEL_OFFSET(bChannel, MUSB_HSDMA_ADDRESS),
-		dma_addr);
-	musb_writel(mbase,
-		MUSB_HSDMA_CHANNEL_OFFSET(bChannel, MUSB_HSDMA_COUNT),
-		len);
-
-	/* control (this should start things) */
-	musb_writew(mbase,
-		MUSB_HSDMA_CHANNEL_OFFSET(bChannel, MUSB_HSDMA_CONTROL),
-		csr);
+		csr |= (pImplChannel->epnum << MUSB_HSDMA_ENDPOINT_SHIFT)
+			| (1 << MUSB_HSDMA_ENABLE_SHIFT)
+			| (1 << MUSB_HSDMA_IRQENABLE_SHIFT)
+			| (pImplChannel->transmit
+					? (1 << MUSB_HSDMA_TRANSMIT_SHIFT)
+					: 0);
+
+		/* address/count */
+		musb_writel(mbase,
+			MUSB_HSDMA_CHANNEL_OFFSET(bChannel, MUSB_HSDMA_ADDRESS),
+			dma_addr);
+		musb_writel(mbase,
+			MUSB_HSDMA_CHANNEL_OFFSET(bChannel, MUSB_HSDMA_COUNT),
+			len);
+
+		/* control (this should start things) */
+		musb_writew(mbase,
+			MUSB_HSDMA_CHANNEL_OFFSET(bChannel, MUSB_HSDMA_CONTROL),
+			csr);
+	} /* Mentor DMA */
 }
 
 static int dma_channel_program(struct dma_channel *pChannel,
@@ -265,6 +364,12 @@ static int dma_channel_abort(struct dma_
 				MUSB_EP_OFFSET(pImplChannel->epnum, MUSB_TXCSR),
 				csr);
 		} else {
+			if (pImplChannel->sysdma_channel != -1) {
+				omap_stop_dma(pImplChannel->sysdma_channel);
+				omap_free_dma(pImplChannel->sysdma_channel);
+				pImplChannel->sysdma_channel = -1;
+			}
+
 			csr = musb_readw(mbase,
 				MUSB_EP_OFFSET(pImplChannel->epnum, MUSB_RXCSR));
 			csr &= ~(MUSB_RXCSR_AUTOCLEAR |
Index: linux-omap-2.6/drivers/usb/musb/Kconfig
===================================================================
--- linux-omap-2.6.orig/drivers/usb/musb/Kconfig	2008-07-28 10:54:37.000000000 +0530
+++ linux-omap-2.6/drivers/usb/musb/Kconfig	2008-08-12 13:18:34.000000000 +0530
@@ -150,6 +150,14 @@ config USB_INVENTRA_DMA
 	help
 	  Enable DMA transfers using Mentor's engine.
 
+config MUSB_USE_SYSTEM_DMA_RX
+	bool 'Use System DMA for RX endpoints'
+	depends on USB_MUSB_HDRC && USB_INVENTRA_DMA
+	help
+	  MUSB RTL version 1.4 has a hardware issue when TX and RX DMA
+	  channels are simultaneously enabled. To work around this issue,
+	  you can choose to use System DMA for RX channels.
+
 config USB_TI_CPPI_DMA
 	bool
 	depends on USB_MUSB_HDRC && !MUSB_PIO_ONLY--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html