xref: /openbmc/linux/arch/arm/mach-omap2/dma.c (revision 1a59d1b8)
1 /*
2  * OMAP2+ DMA driver
3  *
4  * Copyright (C) 2003 - 2008 Nokia Corporation
5  * Author: Juha Yrjölä <juha.yrjola@nokia.com>
6  * DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com>
7  * Graphics DMA and LCD DMA graphics tranformations
8  * by Imre Deak <imre.deak@nokia.com>
9  * OMAP2/3 support Copyright (C) 2004-2007 Texas Instruments, Inc.
10  * Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc.
11  *
12  * Copyright (C) 2009 Texas Instruments
13  * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
14  *
15  * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
16  * Converted DMA library into platform driver
17  *	- G, Manjunath Kondaiah <manjugk@ti.com>
18  *
19  * This program is free software; you can redistribute it and/or modify
20  * it under the terms of the GNU General Public License version 2 as
21  * published by the Free Software Foundation.
22  */
23 
24 #include <linux/err.h>
25 #include <linux/io.h>
26 #include <linux/slab.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/device.h>
30 #include <linux/dma-mapping.h>
31 #include <linux/dmaengine.h>
32 #include <linux/of.h>
33 #include <linux/omap-dma.h>
34 
35 #include "soc.h"
36 #include "omap_hwmod.h"
37 #include "omap_device.h"
38 
39 static enum omap_reg_offsets dma_common_ch_end;
40 
41 static const struct omap_dma_reg reg_map[] = {
42 	[REVISION]	= { 0x0000, 0x00, OMAP_DMA_REG_32BIT },
43 	[GCR]		= { 0x0078, 0x00, OMAP_DMA_REG_32BIT },
44 	[IRQSTATUS_L0]	= { 0x0008, 0x00, OMAP_DMA_REG_32BIT },
45 	[IRQSTATUS_L1]	= { 0x000c, 0x00, OMAP_DMA_REG_32BIT },
46 	[IRQSTATUS_L2]	= { 0x0010, 0x00, OMAP_DMA_REG_32BIT },
47 	[IRQSTATUS_L3]	= { 0x0014, 0x00, OMAP_DMA_REG_32BIT },
48 	[IRQENABLE_L0]	= { 0x0018, 0x00, OMAP_DMA_REG_32BIT },
49 	[IRQENABLE_L1]	= { 0x001c, 0x00, OMAP_DMA_REG_32BIT },
50 	[IRQENABLE_L2]	= { 0x0020, 0x00, OMAP_DMA_REG_32BIT },
51 	[IRQENABLE_L3]	= { 0x0024, 0x00, OMAP_DMA_REG_32BIT },
52 	[SYSSTATUS]	= { 0x0028, 0x00, OMAP_DMA_REG_32BIT },
53 	[OCP_SYSCONFIG]	= { 0x002c, 0x00, OMAP_DMA_REG_32BIT },
54 	[CAPS_0]	= { 0x0064, 0x00, OMAP_DMA_REG_32BIT },
55 	[CAPS_2]	= { 0x006c, 0x00, OMAP_DMA_REG_32BIT },
56 	[CAPS_3]	= { 0x0070, 0x00, OMAP_DMA_REG_32BIT },
57 	[CAPS_4]	= { 0x0074, 0x00, OMAP_DMA_REG_32BIT },
58 
59 	/* Common register offsets */
60 	[CCR]		= { 0x0080, 0x60, OMAP_DMA_REG_32BIT },
61 	[CLNK_CTRL]	= { 0x0084, 0x60, OMAP_DMA_REG_32BIT },
62 	[CICR]		= { 0x0088, 0x60, OMAP_DMA_REG_32BIT },
63 	[CSR]		= { 0x008c, 0x60, OMAP_DMA_REG_32BIT },
64 	[CSDP]		= { 0x0090, 0x60, OMAP_DMA_REG_32BIT },
65 	[CEN]		= { 0x0094, 0x60, OMAP_DMA_REG_32BIT },
66 	[CFN]		= { 0x0098, 0x60, OMAP_DMA_REG_32BIT },
67 	[CSEI]		= { 0x00a4, 0x60, OMAP_DMA_REG_32BIT },
68 	[CSFI]		= { 0x00a8, 0x60, OMAP_DMA_REG_32BIT },
69 	[CDEI]		= { 0x00ac, 0x60, OMAP_DMA_REG_32BIT },
70 	[CDFI]		= { 0x00b0, 0x60, OMAP_DMA_REG_32BIT },
71 	[CSAC]		= { 0x00b4, 0x60, OMAP_DMA_REG_32BIT },
72 	[CDAC]		= { 0x00b8, 0x60, OMAP_DMA_REG_32BIT },
73 
74 	/* Channel specific register offsets */
75 	[CSSA]		= { 0x009c, 0x60, OMAP_DMA_REG_32BIT },
76 	[CDSA]		= { 0x00a0, 0x60, OMAP_DMA_REG_32BIT },
77 	[CCEN]		= { 0x00bc, 0x60, OMAP_DMA_REG_32BIT },
78 	[CCFN]		= { 0x00c0, 0x60, OMAP_DMA_REG_32BIT },
79 	[COLOR]		= { 0x00c4, 0x60, OMAP_DMA_REG_32BIT },
80 
81 	/* OMAP4 specific registers */
82 	[CDP]		= { 0x00d0, 0x60, OMAP_DMA_REG_32BIT },
83 	[CNDP]		= { 0x00d4, 0x60, OMAP_DMA_REG_32BIT },
84 	[CCDN]		= { 0x00d8, 0x60, OMAP_DMA_REG_32BIT },
85 };
86 
87 static void __iomem *dma_base;
88 static inline void dma_write(u32 val, int reg, int lch)
89 {
90 	void __iomem *addr = dma_base;
91 
92 	addr += reg_map[reg].offset;
93 	addr += reg_map[reg].stride * lch;
94 
95 	writel_relaxed(val, addr);
96 }
97 
98 static inline u32 dma_read(int reg, int lch)
99 {
100 	void __iomem *addr = dma_base;
101 
102 	addr += reg_map[reg].offset;
103 	addr += reg_map[reg].stride * lch;
104 
105 	return readl_relaxed(addr);
106 }
107 
108 static void omap2_clear_dma(int lch)
109 {
110 	int i;
111 
112 	for (i = CSDP; i <= dma_common_ch_end; i += 1)
113 		dma_write(0, i, lch);
114 }
115 
116 static void omap2_show_dma_caps(void)
117 {
118 	u8 revision = dma_read(REVISION, 0) & 0xff;
119 	printk(KERN_INFO "OMAP DMA hardware revision %d.%d\n",
120 				revision >> 4, revision & 0xf);
121 }
122 
123 static unsigned configure_dma_errata(void)
124 {
125 	unsigned errata = 0;
126 
127 	/*
128 	 * Errata applicable for OMAP2430ES1.0 and all omap2420
129 	 *
130 	 * I.
131 	 * Erratum ID: Not Available
132 	 * Inter Frame DMA buffering issue DMA will wrongly
133 	 * buffer elements if packing and bursting is enabled. This might
134 	 * result in data gets stalled in FIFO at the end of the block.
135 	 * Workaround: DMA channels must have BUFFERING_DISABLED bit set to
136 	 * guarantee no data will stay in the DMA FIFO in case inter frame
137 	 * buffering occurs
138 	 *
139 	 * II.
140 	 * Erratum ID: Not Available
141 	 * DMA may hang when several channels are used in parallel
142 	 * In the following configuration, DMA channel hanging can occur:
143 	 * a. Channel i, hardware synchronized, is enabled
144 	 * b. Another channel (Channel x), software synchronized, is enabled.
145 	 * c. Channel i is disabled before end of transfer
146 	 * d. Channel i is reenabled.
147 	 * e. Steps 1 to 4 are repeated a certain number of times.
148 	 * f. A third channel (Channel y), software synchronized, is enabled.
149 	 * Channel x and Channel y may hang immediately after step 'f'.
150 	 * Workaround:
151 	 * For any channel used - make sure NextLCH_ID is set to the value j.
152 	 */
153 	if (cpu_is_omap2420() || (cpu_is_omap2430() &&
154 				(omap_type() == OMAP2430_REV_ES1_0))) {
155 
156 		SET_DMA_ERRATA(DMA_ERRATA_IFRAME_BUFFERING);
157 		SET_DMA_ERRATA(DMA_ERRATA_PARALLEL_CHANNELS);
158 	}
159 
160 	/*
161 	 * Erratum ID: i378: OMAP2+: sDMA Channel is not disabled
162 	 * after a transaction error.
163 	 * Workaround: SW should explicitely disable the channel.
164 	 */
165 	if (cpu_class_is_omap2())
166 		SET_DMA_ERRATA(DMA_ERRATA_i378);
167 
168 	/*
169 	 * Erratum ID: i541: sDMA FIFO draining does not finish
170 	 * If sDMA channel is disabled on the fly, sDMA enters standby even
171 	 * through FIFO Drain is still in progress
172 	 * Workaround: Put sDMA in NoStandby more before a logical channel is
173 	 * disabled, then put it back to SmartStandby right after the channel
174 	 * finishes FIFO draining.
175 	 */
176 	if (cpu_is_omap34xx())
177 		SET_DMA_ERRATA(DMA_ERRATA_i541);
178 
179 	/*
180 	 * Erratum ID: i88 : Special programming model needed to disable DMA
181 	 * before end of block.
182 	 * Workaround: software must ensure that the DMA is configured in No
183 	 * Standby mode(DMAx_OCP_SYSCONFIG.MIDLEMODE = "01")
184 	 */
185 	if (omap_type() == OMAP3430_REV_ES1_0)
186 		SET_DMA_ERRATA(DMA_ERRATA_i88);
187 
188 	/*
189 	 * Erratum 3.2/3.3: sometimes 0 is returned if CSAC/CDAC is
190 	 * read before the DMA controller finished disabling the channel.
191 	 */
192 	SET_DMA_ERRATA(DMA_ERRATA_3_3);
193 
194 	/*
195 	 * Erratum ID: Not Available
196 	 * A bug in ROM code leaves IRQ status for channels 0 and 1 uncleared
197 	 * after secure sram context save and restore.
198 	 * Work around: Hence we need to manually clear those IRQs to avoid
199 	 * spurious interrupts. This affects only secure devices.
200 	 */
201 	if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
202 		SET_DMA_ERRATA(DMA_ROMCODE_BUG);
203 
204 	return errata;
205 }
206 
207 static const struct dma_slave_map omap24xx_sdma_dt_map[] = {
208 	/* external DMA requests when tusb6010 is used */
209 	{ "musb-hdrc.1.auto", "dmareq0", SDMA_FILTER_PARAM(2) },
210 	{ "musb-hdrc.1.auto", "dmareq1", SDMA_FILTER_PARAM(3) },
211 	{ "musb-hdrc.1.auto", "dmareq2", SDMA_FILTER_PARAM(14) }, /* OMAP2420 only */
212 	{ "musb-hdrc.1.auto", "dmareq3", SDMA_FILTER_PARAM(15) }, /* OMAP2420 only */
213 	{ "musb-hdrc.1.auto", "dmareq4", SDMA_FILTER_PARAM(16) }, /* OMAP2420 only */
214 	{ "musb-hdrc.1.auto", "dmareq5", SDMA_FILTER_PARAM(64) }, /* OMAP2420 only */
215 };
216 
217 static struct omap_system_dma_plat_info dma_plat_info __initdata = {
218 	.reg_map	= reg_map,
219 	.channel_stride	= 0x60,
220 	.show_dma_caps	= omap2_show_dma_caps,
221 	.clear_dma	= omap2_clear_dma,
222 	.dma_write	= dma_write,
223 	.dma_read	= dma_read,
224 };
225 
226 static struct platform_device_info omap_dma_dev_info __initdata = {
227 	.name = "omap-dma-engine",
228 	.id = -1,
229 	.dma_mask = DMA_BIT_MASK(32),
230 };
231 
232 /* One time initializations */
233 static int __init omap2_system_dma_init_dev(struct omap_hwmod *oh, void *unused)
234 {
235 	struct platform_device			*pdev;
236 	struct omap_system_dma_plat_info	p;
237 	struct omap_dma_dev_attr		*d;
238 	struct resource				*mem;
239 	char					*name = "omap_dma_system";
240 
241 	p = dma_plat_info;
242 	p.dma_attr = (struct omap_dma_dev_attr *)oh->dev_attr;
243 	p.errata = configure_dma_errata();
244 
245 	if (soc_is_omap24xx()) {
246 		/* DMA slave map for drivers not yet converted to DT */
247 		p.slave_map = omap24xx_sdma_dt_map;
248 		p.slavecnt = ARRAY_SIZE(omap24xx_sdma_dt_map);
249 	}
250 
251 	pdev = omap_device_build(name, 0, oh, &p, sizeof(p));
252 	if (IS_ERR(pdev)) {
253 		pr_err("%s: Can't build omap_device for %s:%s.\n",
254 			__func__, name, oh->name);
255 		return PTR_ERR(pdev);
256 	}
257 
258 	omap_dma_dev_info.res = pdev->resource;
259 	omap_dma_dev_info.num_res = pdev->num_resources;
260 
261 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
262 	if (!mem) {
263 		dev_err(&pdev->dev, "%s: no mem resource\n", __func__);
264 		return -EINVAL;
265 	}
266 
267 	dma_base = ioremap(mem->start, resource_size(mem));
268 	if (!dma_base) {
269 		dev_err(&pdev->dev, "%s: ioremap fail\n", __func__);
270 		return -ENOMEM;
271 	}
272 
273 	d = oh->dev_attr;
274 
275 	if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
276 		d->dev_caps |= HS_CHANNELS_RESERVED;
277 
278 	if (platform_get_irq_byname(pdev, "0") < 0)
279 		d->dev_caps |= DMA_ENGINE_HANDLE_IRQ;
280 
281 	/* Check the capabilities register for descriptor loading feature */
282 	if (dma_read(CAPS_0, 0) & DMA_HAS_DESCRIPTOR_CAPS)
283 		dma_common_ch_end = CCDN;
284 	else
285 		dma_common_ch_end = CCFN;
286 
287 	return 0;
288 }
289 
290 static int __init omap2_system_dma_init(void)
291 {
292 	return omap_hwmod_for_each_by_class("dma",
293 			omap2_system_dma_init_dev, NULL);
294 }
295 omap_arch_initcall(omap2_system_dma_init);
296