xref: /openbmc/linux/arch/arm/mach-omap2/dma.c (revision 2127c01b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * OMAP2+ DMA driver
4  *
5  * Copyright (C) 2003 - 2008 Nokia Corporation
6  * Author: Juha Yrjölä <juha.yrjola@nokia.com>
7  * DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com>
8  * Graphics DMA and LCD DMA graphics tranformations
9  * by Imre Deak <imre.deak@nokia.com>
10  * OMAP2/3 support Copyright (C) 2004-2007 Texas Instruments, Inc.
11  * Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc.
12  *
13  * Copyright (C) 2009 Texas Instruments
14  * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
15  *
16  * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
17  * Converted DMA library into platform driver
18  *	- G, Manjunath Kondaiah <manjugk@ti.com>
19  */
20 
21 #include <linux/err.h>
22 #include <linux/io.h>
23 #include <linux/slab.h>
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/device.h>
27 #include <linux/dma-mapping.h>
28 #include <linux/dmaengine.h>
29 #include <linux/of.h>
30 #include <linux/omap-dma.h>
31 
32 #include "soc.h"
33 #include "omap_hwmod.h"
34 #include "omap_device.h"
35 
36 static enum omap_reg_offsets dma_common_ch_end;
37 
38 static const struct omap_dma_reg reg_map[] = {
39 	[REVISION]	= { 0x0000, 0x00, OMAP_DMA_REG_32BIT },
40 	[GCR]		= { 0x0078, 0x00, OMAP_DMA_REG_32BIT },
41 	[IRQSTATUS_L0]	= { 0x0008, 0x00, OMAP_DMA_REG_32BIT },
42 	[IRQSTATUS_L1]	= { 0x000c, 0x00, OMAP_DMA_REG_32BIT },
43 	[IRQSTATUS_L2]	= { 0x0010, 0x00, OMAP_DMA_REG_32BIT },
44 	[IRQSTATUS_L3]	= { 0x0014, 0x00, OMAP_DMA_REG_32BIT },
45 	[IRQENABLE_L0]	= { 0x0018, 0x00, OMAP_DMA_REG_32BIT },
46 	[IRQENABLE_L1]	= { 0x001c, 0x00, OMAP_DMA_REG_32BIT },
47 	[IRQENABLE_L2]	= { 0x0020, 0x00, OMAP_DMA_REG_32BIT },
48 	[IRQENABLE_L3]	= { 0x0024, 0x00, OMAP_DMA_REG_32BIT },
49 	[SYSSTATUS]	= { 0x0028, 0x00, OMAP_DMA_REG_32BIT },
50 	[OCP_SYSCONFIG]	= { 0x002c, 0x00, OMAP_DMA_REG_32BIT },
51 	[CAPS_0]	= { 0x0064, 0x00, OMAP_DMA_REG_32BIT },
52 	[CAPS_2]	= { 0x006c, 0x00, OMAP_DMA_REG_32BIT },
53 	[CAPS_3]	= { 0x0070, 0x00, OMAP_DMA_REG_32BIT },
54 	[CAPS_4]	= { 0x0074, 0x00, OMAP_DMA_REG_32BIT },
55 
56 	/* Common register offsets */
57 	[CCR]		= { 0x0080, 0x60, OMAP_DMA_REG_32BIT },
58 	[CLNK_CTRL]	= { 0x0084, 0x60, OMAP_DMA_REG_32BIT },
59 	[CICR]		= { 0x0088, 0x60, OMAP_DMA_REG_32BIT },
60 	[CSR]		= { 0x008c, 0x60, OMAP_DMA_REG_32BIT },
61 	[CSDP]		= { 0x0090, 0x60, OMAP_DMA_REG_32BIT },
62 	[CEN]		= { 0x0094, 0x60, OMAP_DMA_REG_32BIT },
63 	[CFN]		= { 0x0098, 0x60, OMAP_DMA_REG_32BIT },
64 	[CSEI]		= { 0x00a4, 0x60, OMAP_DMA_REG_32BIT },
65 	[CSFI]		= { 0x00a8, 0x60, OMAP_DMA_REG_32BIT },
66 	[CDEI]		= { 0x00ac, 0x60, OMAP_DMA_REG_32BIT },
67 	[CDFI]		= { 0x00b0, 0x60, OMAP_DMA_REG_32BIT },
68 	[CSAC]		= { 0x00b4, 0x60, OMAP_DMA_REG_32BIT },
69 	[CDAC]		= { 0x00b8, 0x60, OMAP_DMA_REG_32BIT },
70 
71 	/* Channel specific register offsets */
72 	[CSSA]		= { 0x009c, 0x60, OMAP_DMA_REG_32BIT },
73 	[CDSA]		= { 0x00a0, 0x60, OMAP_DMA_REG_32BIT },
74 	[CCEN]		= { 0x00bc, 0x60, OMAP_DMA_REG_32BIT },
75 	[CCFN]		= { 0x00c0, 0x60, OMAP_DMA_REG_32BIT },
76 	[COLOR]		= { 0x00c4, 0x60, OMAP_DMA_REG_32BIT },
77 
78 	/* OMAP4 specific registers */
79 	[CDP]		= { 0x00d0, 0x60, OMAP_DMA_REG_32BIT },
80 	[CNDP]		= { 0x00d4, 0x60, OMAP_DMA_REG_32BIT },
81 	[CCDN]		= { 0x00d8, 0x60, OMAP_DMA_REG_32BIT },
82 };
83 
84 static void __iomem *dma_base;
85 static inline void dma_write(u32 val, int reg, int lch)
86 {
87 	void __iomem *addr = dma_base;
88 
89 	addr += reg_map[reg].offset;
90 	addr += reg_map[reg].stride * lch;
91 
92 	writel_relaxed(val, addr);
93 }
94 
95 static inline u32 dma_read(int reg, int lch)
96 {
97 	void __iomem *addr = dma_base;
98 
99 	addr += reg_map[reg].offset;
100 	addr += reg_map[reg].stride * lch;
101 
102 	return readl_relaxed(addr);
103 }
104 
105 static void omap2_clear_dma(int lch)
106 {
107 	int i;
108 
109 	for (i = CSDP; i <= dma_common_ch_end; i += 1)
110 		dma_write(0, i, lch);
111 }
112 
113 static void omap2_show_dma_caps(void)
114 {
115 	u8 revision = dma_read(REVISION, 0) & 0xff;
116 	printk(KERN_INFO "OMAP DMA hardware revision %d.%d\n",
117 				revision >> 4, revision & 0xf);
118 }
119 
120 static unsigned configure_dma_errata(void)
121 {
122 	unsigned errata = 0;
123 
124 	/*
125 	 * Errata applicable for OMAP2430ES1.0 and all omap2420
126 	 *
127 	 * I.
128 	 * Erratum ID: Not Available
129 	 * Inter Frame DMA buffering issue DMA will wrongly
130 	 * buffer elements if packing and bursting is enabled. This might
131 	 * result in data gets stalled in FIFO at the end of the block.
132 	 * Workaround: DMA channels must have BUFFERING_DISABLED bit set to
133 	 * guarantee no data will stay in the DMA FIFO in case inter frame
134 	 * buffering occurs
135 	 *
136 	 * II.
137 	 * Erratum ID: Not Available
138 	 * DMA may hang when several channels are used in parallel
139 	 * In the following configuration, DMA channel hanging can occur:
140 	 * a. Channel i, hardware synchronized, is enabled
141 	 * b. Another channel (Channel x), software synchronized, is enabled.
142 	 * c. Channel i is disabled before end of transfer
143 	 * d. Channel i is reenabled.
144 	 * e. Steps 1 to 4 are repeated a certain number of times.
145 	 * f. A third channel (Channel y), software synchronized, is enabled.
146 	 * Channel x and Channel y may hang immediately after step 'f'.
147 	 * Workaround:
148 	 * For any channel used - make sure NextLCH_ID is set to the value j.
149 	 */
150 	if (cpu_is_omap2420() || (cpu_is_omap2430() &&
151 				(omap_type() == OMAP2430_REV_ES1_0))) {
152 
153 		SET_DMA_ERRATA(DMA_ERRATA_IFRAME_BUFFERING);
154 		SET_DMA_ERRATA(DMA_ERRATA_PARALLEL_CHANNELS);
155 	}
156 
157 	/*
158 	 * Erratum ID: i378: OMAP2+: sDMA Channel is not disabled
159 	 * after a transaction error.
160 	 * Workaround: SW should explicitely disable the channel.
161 	 */
162 	if (cpu_class_is_omap2())
163 		SET_DMA_ERRATA(DMA_ERRATA_i378);
164 
165 	/*
166 	 * Erratum ID: i541: sDMA FIFO draining does not finish
167 	 * If sDMA channel is disabled on the fly, sDMA enters standby even
168 	 * through FIFO Drain is still in progress
169 	 * Workaround: Put sDMA in NoStandby more before a logical channel is
170 	 * disabled, then put it back to SmartStandby right after the channel
171 	 * finishes FIFO draining.
172 	 */
173 	if (cpu_is_omap34xx())
174 		SET_DMA_ERRATA(DMA_ERRATA_i541);
175 
176 	/*
177 	 * Erratum ID: i88 : Special programming model needed to disable DMA
178 	 * before end of block.
179 	 * Workaround: software must ensure that the DMA is configured in No
180 	 * Standby mode(DMAx_OCP_SYSCONFIG.MIDLEMODE = "01")
181 	 */
182 	if (omap_type() == OMAP3430_REV_ES1_0)
183 		SET_DMA_ERRATA(DMA_ERRATA_i88);
184 
185 	/*
186 	 * Erratum 3.2/3.3: sometimes 0 is returned if CSAC/CDAC is
187 	 * read before the DMA controller finished disabling the channel.
188 	 */
189 	SET_DMA_ERRATA(DMA_ERRATA_3_3);
190 
191 	/*
192 	 * Erratum ID: Not Available
193 	 * A bug in ROM code leaves IRQ status for channels 0 and 1 uncleared
194 	 * after secure sram context save and restore.
195 	 * Work around: Hence we need to manually clear those IRQs to avoid
196 	 * spurious interrupts. This affects only secure devices.
197 	 */
198 	if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
199 		SET_DMA_ERRATA(DMA_ROMCODE_BUG);
200 
201 	return errata;
202 }
203 
204 static const struct dma_slave_map omap24xx_sdma_dt_map[] = {
205 	/* external DMA requests when tusb6010 is used */
206 	{ "musb-hdrc.1.auto", "dmareq0", SDMA_FILTER_PARAM(2) },
207 	{ "musb-hdrc.1.auto", "dmareq1", SDMA_FILTER_PARAM(3) },
208 	{ "musb-hdrc.1.auto", "dmareq2", SDMA_FILTER_PARAM(14) }, /* OMAP2420 only */
209 	{ "musb-hdrc.1.auto", "dmareq3", SDMA_FILTER_PARAM(15) }, /* OMAP2420 only */
210 	{ "musb-hdrc.1.auto", "dmareq4", SDMA_FILTER_PARAM(16) }, /* OMAP2420 only */
211 	{ "musb-hdrc.1.auto", "dmareq5", SDMA_FILTER_PARAM(64) }, /* OMAP2420 only */
212 };
213 
214 static struct omap_system_dma_plat_info dma_plat_info __initdata = {
215 	.reg_map	= reg_map,
216 	.channel_stride	= 0x60,
217 	.show_dma_caps	= omap2_show_dma_caps,
218 	.clear_dma	= omap2_clear_dma,
219 	.dma_write	= dma_write,
220 	.dma_read	= dma_read,
221 };
222 
223 static struct platform_device_info omap_dma_dev_info __initdata = {
224 	.name = "omap-dma-engine",
225 	.id = -1,
226 	.dma_mask = DMA_BIT_MASK(32),
227 };
228 
229 /* One time initializations */
230 static int __init omap2_system_dma_init_dev(struct omap_hwmod *oh, void *unused)
231 {
232 	struct platform_device			*pdev;
233 	struct omap_system_dma_plat_info	p;
234 	struct omap_dma_dev_attr		*d;
235 	struct resource				*mem;
236 	char					*name = "omap_dma_system";
237 
238 	p = dma_plat_info;
239 	p.dma_attr = (struct omap_dma_dev_attr *)oh->dev_attr;
240 	p.errata = configure_dma_errata();
241 
242 	if (soc_is_omap24xx()) {
243 		/* DMA slave map for drivers not yet converted to DT */
244 		p.slave_map = omap24xx_sdma_dt_map;
245 		p.slavecnt = ARRAY_SIZE(omap24xx_sdma_dt_map);
246 	}
247 
248 	pdev = omap_device_build(name, 0, oh, &p, sizeof(p));
249 	if (IS_ERR(pdev)) {
250 		pr_err("%s: Can't build omap_device for %s:%s.\n",
251 			__func__, name, oh->name);
252 		return PTR_ERR(pdev);
253 	}
254 
255 	omap_dma_dev_info.res = pdev->resource;
256 	omap_dma_dev_info.num_res = pdev->num_resources;
257 
258 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
259 	if (!mem) {
260 		dev_err(&pdev->dev, "%s: no mem resource\n", __func__);
261 		return -EINVAL;
262 	}
263 
264 	dma_base = ioremap(mem->start, resource_size(mem));
265 	if (!dma_base) {
266 		dev_err(&pdev->dev, "%s: ioremap fail\n", __func__);
267 		return -ENOMEM;
268 	}
269 
270 	d = oh->dev_attr;
271 
272 	if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
273 		d->dev_caps |= HS_CHANNELS_RESERVED;
274 
275 	if (platform_get_irq_byname(pdev, "0") < 0)
276 		d->dev_caps |= DMA_ENGINE_HANDLE_IRQ;
277 
278 	/* Check the capabilities register for descriptor loading feature */
279 	if (dma_read(CAPS_0, 0) & DMA_HAS_DESCRIPTOR_CAPS)
280 		dma_common_ch_end = CCDN;
281 	else
282 		dma_common_ch_end = CCFN;
283 
284 	return 0;
285 }
286 
287 static int __init omap2_system_dma_init(void)
288 {
289 	return omap_hwmod_for_each_by_class("dma",
290 			omap2_system_dma_init_dev, NULL);
291 }
292 omap_arch_initcall(omap2_system_dma_init);
293