1 /*
2 * Programmable Real-Time Unit Sub System (PRUSS) UIO driver (uio_pruss)
3 *
4 * This driver exports PRUSS host event out interrupts and PRUSS, L3 RAM,
5 * and DDR RAM to user space for applications interacting with PRUSS firmware
6 *
7 * Copyright (C) 2010-11 Texas Instruments Incorporated - http://www.ti.com/
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation version 2.
12 *
13 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
14 * kind, whether express or implied; without even the implied warranty
15 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 */
18 #include <linux/device.h>
19 #include <linux/module.h>
20 #include <linux/moduleparam.h>
21 #include <linux/platform_device.h>
22 #include <linux/uio_driver.h>
23 #include <linux/platform_data/uio_pruss.h>
24 #include <linux/io.h>
25 #include <linux/clk.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/slab.h>
28 #include <mach/sram.h>
29
30 #define DRV_NAME "pruss_uio"
31 #define DRV_VERSION "1.0"
32
33 static int sram_pool_sz = SZ_16K;
34 module_param(sram_pool_sz, int, 0);
35 MODULE_PARM_DESC(sram_pool_sz, "sram pool size to allocate ");
36
37 static int extram_pool_sz = SZ_256K;
38 module_param(extram_pool_sz, int, 0);
39 MODULE_PARM_DESC(extram_pool_sz, "external ram pool size to allocate");
40
41 /*
42 * Host event IRQ numbers from PRUSS - PRUSS can generate up to 8 interrupt
43 * events to AINTC of ARM host processor - which can be used for IPC b/w PRUSS
44 * firmware and user space application, async notification from PRU firmware
45 * to user space application
46 * 3 PRU_EVTOUT0
47 * 4 PRU_EVTOUT1
48 * 5 PRU_EVTOUT2
49 * 6 PRU_EVTOUT3
50 * 7 PRU_EVTOUT4
51 * 8 PRU_EVTOUT5
52 * 9 PRU_EVTOUT6
53 * 10 PRU_EVTOUT7
54 */
55 #define MAX_PRUSS_EVT 8
56
57 #define PINTC_HIDISR 0x0038
58 #define PINTC_HIPIR 0x0900
59 #define HIPIR_NOPEND 0x80000000
60 #define PINTC_HIER 0x1500
61
62 struct uio_pruss_dev {
63 struct uio_info *info;
64 struct clk *pruss_clk;
65 dma_addr_t sram_paddr;
66 dma_addr_t ddr_paddr;
67 void __iomem *prussio_vaddr;
68 void *sram_vaddr;
69 void *ddr_vaddr;
70 unsigned int hostirq_start;
71 unsigned int pintc_base;
72 };
73
pruss_handler(int irq,struct uio_info * info)74 static irqreturn_t pruss_handler(int irq, struct uio_info *info)
75 {
76 struct uio_pruss_dev *gdev = info->priv;
77 int intr_bit = (irq - gdev->hostirq_start + 2);
78 int val, intr_mask = (1 << intr_bit);
79 void __iomem *base = gdev->prussio_vaddr + gdev->pintc_base;
80 void __iomem *intren_reg = base + PINTC_HIER;
81 void __iomem *intrdis_reg = base + PINTC_HIDISR;
82 void __iomem *intrstat_reg = base + PINTC_HIPIR + (intr_bit << 2);
83
84 val = ioread32(intren_reg);
85 /* Is interrupt enabled and active ? */
86 if (!(val & intr_mask) && (ioread32(intrstat_reg) & HIPIR_NOPEND))
87 return IRQ_NONE;
88 /* Disable interrupt */
89 iowrite32(intr_bit, intrdis_reg);
90 return IRQ_HANDLED;
91 }
92
pruss_cleanup(struct platform_device * dev,struct uio_pruss_dev * gdev)93 static void pruss_cleanup(struct platform_device *dev,
94 struct uio_pruss_dev *gdev)
95 {
96 int cnt;
97 struct uio_info *p = gdev->info;
98
99 for (cnt = 0; cnt < MAX_PRUSS_EVT; cnt++, p++) {
100 uio_unregister_device(p);
101 kfree(p->name);
102 }
103 iounmap(gdev->prussio_vaddr);
104 if (gdev->ddr_vaddr) {
105 dma_free_coherent(&dev->dev, extram_pool_sz, gdev->ddr_vaddr,
106 gdev->ddr_paddr);
107 }
108 if (gdev->sram_vaddr)
109 sram_free(gdev->sram_vaddr, sram_pool_sz);
110 kfree(gdev->info);
111 clk_put(gdev->pruss_clk);
112 kfree(gdev);
113 }
114
pruss_probe(struct platform_device * dev)115 static int __devinit pruss_probe(struct platform_device *dev)
116 {
117 struct uio_info *p;
118 struct uio_pruss_dev *gdev;
119 struct resource *regs_prussio;
120 int ret = -ENODEV, cnt = 0, len;
121 struct uio_pruss_pdata *pdata = dev->dev.platform_data;
122
123 gdev = kzalloc(sizeof(struct uio_pruss_dev), GFP_KERNEL);
124 if (!gdev)
125 return -ENOMEM;
126
127 gdev->info = kzalloc(sizeof(*p) * MAX_PRUSS_EVT, GFP_KERNEL);
128 if (!gdev->info) {
129 kfree(gdev);
130 return -ENOMEM;
131 }
132 /* Power on PRU in case its not done as part of boot-loader */
133 gdev->pruss_clk = clk_get(&dev->dev, "pruss");
134 if (IS_ERR(gdev->pruss_clk)) {
135 dev_err(&dev->dev, "Failed to get clock\n");
136 kfree(gdev->info);
137 kfree(gdev);
138 ret = PTR_ERR(gdev->pruss_clk);
139 return ret;
140 } else {
141 clk_enable(gdev->pruss_clk);
142 }
143
144 regs_prussio = platform_get_resource(dev, IORESOURCE_MEM, 0);
145 if (!regs_prussio) {
146 dev_err(&dev->dev, "No PRUSS I/O resource specified\n");
147 goto out_free;
148 }
149
150 if (!regs_prussio->start) {
151 dev_err(&dev->dev, "Invalid memory resource\n");
152 goto out_free;
153 }
154
155 gdev->sram_vaddr = sram_alloc(sram_pool_sz, &(gdev->sram_paddr));
156 if (!gdev->sram_vaddr) {
157 dev_err(&dev->dev, "Could not allocate SRAM pool\n");
158 goto out_free;
159 }
160
161 gdev->ddr_vaddr = dma_alloc_coherent(&dev->dev, extram_pool_sz,
162 &(gdev->ddr_paddr), GFP_KERNEL | GFP_DMA);
163 if (!gdev->ddr_vaddr) {
164 dev_err(&dev->dev, "Could not allocate external memory\n");
165 goto out_free;
166 }
167
168 len = resource_size(regs_prussio);
169 gdev->prussio_vaddr = ioremap(regs_prussio->start, len);
170 if (!gdev->prussio_vaddr) {
171 dev_err(&dev->dev, "Can't remap PRUSS I/O address range\n");
172 goto out_free;
173 }
174
175 gdev->pintc_base = pdata->pintc_base;
176 gdev->hostirq_start = platform_get_irq(dev, 0);
177
178 for (cnt = 0, p = gdev->info; cnt < MAX_PRUSS_EVT; cnt++, p++) {
179 p->mem[0].addr = regs_prussio->start;
180 p->mem[0].size = resource_size(regs_prussio);
181 p->mem[0].memtype = UIO_MEM_PHYS;
182
183 p->mem[1].addr = gdev->sram_paddr;
184 p->mem[1].size = sram_pool_sz;
185 p->mem[1].memtype = UIO_MEM_PHYS;
186
187 p->mem[2].addr = gdev->ddr_paddr;
188 p->mem[2].size = extram_pool_sz;
189 p->mem[2].memtype = UIO_MEM_PHYS;
190
191 p->name = kasprintf(GFP_KERNEL, "pruss_evt%d", cnt);
192 p->version = DRV_VERSION;
193
194 /* Register PRUSS IRQ lines */
195 p->irq = gdev->hostirq_start + cnt;
196 p->handler = pruss_handler;
197 p->priv = gdev;
198
199 ret = uio_register_device(&dev->dev, p);
200 if (ret < 0)
201 goto out_free;
202 }
203
204 platform_set_drvdata(dev, gdev);
205 return 0;
206
207 out_free:
208 pruss_cleanup(dev, gdev);
209 return ret;
210 }
211
pruss_remove(struct platform_device * dev)212 static int __devexit pruss_remove(struct platform_device *dev)
213 {
214 struct uio_pruss_dev *gdev = platform_get_drvdata(dev);
215
216 pruss_cleanup(dev, gdev);
217 platform_set_drvdata(dev, NULL);
218 return 0;
219 }
220
221 static struct platform_driver pruss_driver = {
222 .probe = pruss_probe,
223 .remove = __devexit_p(pruss_remove),
224 .driver = {
225 .name = DRV_NAME,
226 .owner = THIS_MODULE,
227 },
228 };
229
pruss_init_module(void)230 static int __init pruss_init_module(void)
231 {
232 return platform_driver_register(&pruss_driver);
233 }
234
235 module_init(pruss_init_module);
236
pruss_exit_module(void)237 static void __exit pruss_exit_module(void)
238 {
239 platform_driver_unregister(&pruss_driver);
240 }
241
242 module_exit(pruss_exit_module);
243
244 MODULE_LICENSE("GPL v2");
245 MODULE_VERSION(DRV_VERSION);
246 MODULE_AUTHOR("Amit Chatterjee <amit.chatterjee@ti.com>");
247 MODULE_AUTHOR("Pratheesh Gangadhar <pratheesh@ti.com>");
248