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 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 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 } 114 115 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 } 211 212 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 }; 229 230 module_platform_driver(pruss_driver); 231 232 MODULE_LICENSE("GPL v2"); 233 MODULE_VERSION(DRV_VERSION); 234 MODULE_AUTHOR("Amit Chatterjee <amit.chatterjee@ti.com>"); 235 MODULE_AUTHOR("Pratheesh Gangadhar <pratheesh@ti.com>"); 236