summaryrefslogtreecommitdiffstats
path: root/drivers/uio/uio_pruss.c
blob: f8738de342befce9a8853bc4e5937f2d62f66aac (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
/*
 * Programmable Real-Time Unit Sub System (PRUSS) UIO driver (uio_pruss)
 *
 * This driver exports PRUSS host event out interrupts and PRUSS, L3 RAM,
 * and DDR RAM to user space for applications interacting with PRUSS firmware
 *
 * Copyright (C) 2010-11 Texas Instruments Incorporated - http://www.ti.com/
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */
#include <linux/device.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/platform_device.h>
#include <linux/uio_driver.h>
#include <linux/platform_data/uio_pruss.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/genalloc.h>

#define DRV_NAME "pruss_uio"
#define DRV_VERSION "1.0"

static int sram_pool_sz = SZ_16K;
module_param(sram_pool_sz, int, 0);
MODULE_PARM_DESC(sram_pool_sz, "sram pool size to allocate ");

static int extram_pool_sz = SZ_256K;
module_param(extram_pool_sz, int, 0);
MODULE_PARM_DESC(extram_pool_sz, "external ram pool size to allocate");

/*
 * Host event IRQ numbers from PRUSS - PRUSS can generate up to 8 interrupt
 * events to AINTC of ARM host processor - which can be used for IPC b/w PRUSS
 * firmware and user space application, async notification from PRU firmware
 * to user space application
 * 3	PRU_EVTOUT0
 * 4	PRU_EVTOUT1
 * 5	PRU_EVTOUT2
 * 6	PRU_EVTOUT3
 * 7	PRU_EVTOUT4
 * 8	PRU_EVTOUT5
 * 9	PRU_EVTOUT6
 * 10	PRU_EVTOUT7
*/
#define MAX_PRUSS_EVT	8

#define PINTC_HIDISR	0x0038
#define PINTC_HIPIR	0x0900
#define HIPIR_NOPEND	0x80000000
#define PINTC_HIER	0x1500

struct uio_pruss_dev {
	struct uio_info *info;
	struct clk *pruss_clk;
	dma_addr_t sram_paddr;
	dma_addr_t ddr_paddr;
	void __iomem *prussio_vaddr;
	unsigned long sram_vaddr;
	void *ddr_vaddr;
	unsigned int hostirq_start;
	unsigned int pintc_base;
	struct gen_pool *sram_pool;
};

static irqreturn_t pruss_handler(int irq, struct uio_info *info)
{
	struct uio_pruss_dev *gdev = info->priv;
	int intr_bit = (irq - gdev->hostirq_start + 2);
	int val, intr_mask = (1 << intr_bit);
	void __iomem *base = gdev->prussio_vaddr + gdev->pintc_base;
	void __iomem *intren_reg = base + PINTC_HIER;
	void __iomem *intrdis_reg = base + PINTC_HIDISR;
	void __iomem *intrstat_reg = base + PINTC_HIPIR + (intr_bit << 2);

	val = ioread32(intren_reg);
	/* Is interrupt enabled and active ? */
	if (!(val & intr_mask) && (ioread32(intrstat_reg) & HIPIR_NOPEND))
		return IRQ_NONE;
	/* Disable interrupt */
	iowrite32(intr_bit, intrdis_reg);
	return IRQ_HANDLED;
}

static void pruss_cleanup(struct platform_device *dev,
			struct uio_pruss_dev *gdev)
{
	int cnt;
	struct uio_info *p = gdev->info;

	for (cnt = 0; cnt < MAX_PRUSS_EVT; cnt++, p++) {
		uio_unregister_device(p);
		kfree(p->name);
	}
	iounmap(gdev->prussio_vaddr);
	if (gdev->ddr_vaddr) {
		dma_free_coherent(&dev->dev, extram_pool_sz, gdev->ddr_vaddr,
			gdev->ddr_paddr);
	}
	if (gdev->sram_vaddr)
		gen_pool_free(gdev->sram_pool,
			      gdev->sram_vaddr,
			      sram_pool_sz);
	kfree(gdev->info);
	clk_put(gdev->pruss_clk);
	kfree(gdev);
}

static int __devinit pruss_probe(struct platform_device *dev)
{
	struct uio_info *p;
	struct uio_pruss_dev *gdev;
	struct resource *regs_prussio;
	int ret = -ENODEV, cnt = 0, len;
	struct uio_pruss_pdata *pdata = dev->dev.platform_data;

	gdev = kzalloc(sizeof(struct uio_pruss_dev), GFP_KERNEL);
	if (!gdev)
		return -ENOMEM;

	gdev->info = kzalloc(sizeof(*p) * MAX_PRUSS_EVT, GFP_KERNEL);
	if (!gdev->info) {
		kfree(gdev);
		return -ENOMEM;
	}
	/* Power on PRU in case its not done as part of boot-loader */
	gdev->pruss_clk = clk_get(&dev->dev, "pruss");
	if (IS_ERR(gdev->pruss_clk)) {
		dev_err(&dev->dev, "Failed to get clock\n");
		kfree(gdev->info);
		kfree(gdev);
		ret = PTR_ERR(gdev->pruss_clk);
		return ret;
	} else {
		clk_enable(gdev->pruss_clk);
	}

	regs_prussio = platform_get_resource(dev, IORESOURCE_MEM, 0);
	if (!regs_prussio) {
		dev_err(&dev->dev, "No PRUSS I/O resource specified\n");
		goto out_free;
	}

	if (!regs_prussio->start) {
		dev_err(&dev->dev, "Invalid memory resource\n");
		goto out_free;
	}

	if (pdata->sram_pool) {
		gdev->sram_pool = pdata->sram_pool;
		gdev->sram_vaddr =
			gen_pool_alloc(gdev->sram_pool, sram_pool_sz);
		if (!gdev->sram_vaddr) {
			dev_err(&dev->dev, "Could not allocate SRAM pool\n");
			goto out_free;
		}
		gdev->sram_paddr =
			gen_pool_virt_to_phys(gdev->sram_pool,
					      gdev->sram_vaddr);
	}

	gdev->ddr_vaddr = dma_alloc_coherent(&dev->dev, extram_pool_sz,
				&(gdev->ddr_paddr), GFP_KERNEL | GFP_DMA);
	if (!gdev->ddr_vaddr) {
		dev_err(&dev->dev, "Could not allocate external memory\n");
		goto out_free;
	}

	len = resource_size(regs_prussio);
	gdev->prussio_vaddr = ioremap(regs_prussio->start, len);
	if (!gdev->prussio_vaddr) {
		dev_err(&dev->dev, "Can't remap PRUSS I/O  address range\n");
		goto out_free;
	}

	gdev->pintc_base = pdata->pintc_base;
	gdev->hostirq_start = platform_get_irq(dev, 0);

	for (cnt = 0, p = gdev->info; cnt < MAX_PRUSS_EVT; cnt++, p++) {
		p->mem[0].addr = regs_prussio->start;
		p->mem[0].size = resource_size(regs_prussio);
		p->mem[0].memtype = UIO_MEM_PHYS;

		p->mem[1].addr = gdev->sram_paddr;
		p->mem[1].size = sram_pool_sz;
		p->mem[1].memtype = UIO_MEM_PHYS;

		p->mem[2].addr = gdev->ddr_paddr;
		p->mem[2].size = extram_pool_sz;
		p->mem[2].memtype = UIO_MEM_PHYS;

		p->name = kasprintf(GFP_KERNEL, "pruss_evt%d", cnt);
		p->version = DRV_VERSION;

		/* Register PRUSS IRQ lines */
		p->irq = gdev->hostirq_start + cnt;
		p->handler = pruss_handler;
		p->priv = gdev;

		ret = uio_register_device(&dev->dev, p);
		if (ret < 0)
			goto out_free;
	}

	platform_set_drvdata(dev, gdev);
	return 0;

out_free:
	pruss_cleanup(dev, gdev);
	return ret;
}

static int __devexit pruss_remove(struct platform_device *dev)
{
	struct uio_pruss_dev *gdev = platform_get_drvdata(dev);

	pruss_cleanup(dev, gdev);
	platform_set_drvdata(dev, NULL);
	return 0;
}

static struct platform_driver pruss_driver = {
	.probe = pruss_probe,
	.remove = __devexit_p(pruss_remove),
	.driver = {
		   .name = DRV_NAME,
		   .owner = THIS_MODULE,
		   },
};

module_platform_driver(pruss_driver);

MODULE_LICENSE("GPL v2");
MODULE_VERSION(DRV_VERSION);
MODULE_AUTHOR("Amit Chatterjee <amit.chatterjee@ti.com>");
MODULE_AUTHOR("Pratheesh Gangadhar <pratheesh@ti.com>");