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 <linux/genalloc.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 unsigned long sram_vaddr; 69 void *ddr_vaddr; 70 unsigned int hostirq_start; 71 unsigned int pintc_base; 72 struct gen_pool *sram_pool; 73 }; 74 75 static irqreturn_t pruss_handler(int irq, struct uio_info *info) 76 { 77 struct uio_pruss_dev *gdev = info->priv; 78 int intr_bit = (irq - gdev->hostirq_start + 2); 79 int val, intr_mask = (1 << intr_bit); 80 void __iomem *base = gdev->prussio_vaddr + gdev->pintc_base; 81 void __iomem *intren_reg = base + PINTC_HIER; 82 void __iomem *intrdis_reg = base + PINTC_HIDISR; 83 void __iomem *intrstat_reg = base + PINTC_HIPIR + (intr_bit << 2); 84 85 val = ioread32(intren_reg); 86 /* Is interrupt enabled and active ? */ 87 if (!(val & intr_mask) && (ioread32(intrstat_reg) & HIPIR_NOPEND)) 88 return IRQ_NONE; 89 /* Disable interrupt */ 90 iowrite32(intr_bit, intrdis_reg); 91 return IRQ_HANDLED; 92 } 93 94 static void pruss_cleanup(struct device *dev, 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, extram_pool_sz, gdev->ddr_vaddr, 106 gdev->ddr_paddr); 107 } 108 if (gdev->sram_vaddr) 109 gen_pool_free(gdev->sram_pool, 110 gdev->sram_vaddr, 111 sram_pool_sz); 112 kfree(gdev->info); 113 clk_put(gdev->pruss_clk); 114 kfree(gdev); 115 } 116 117 static int pruss_probe(struct platform_device *pdev) 118 { 119 struct uio_info *p; 120 struct uio_pruss_dev *gdev; 121 struct resource *regs_prussio; 122 struct device *dev = &pdev->dev; 123 int ret = -ENODEV, cnt = 0, len; 124 struct uio_pruss_pdata *pdata = dev_get_platdata(dev); 125 126 gdev = kzalloc(sizeof(struct uio_pruss_dev), GFP_KERNEL); 127 if (!gdev) 128 return -ENOMEM; 129 130 gdev->info = kzalloc(sizeof(*p) * MAX_PRUSS_EVT, GFP_KERNEL); 131 if (!gdev->info) { 132 kfree(gdev); 133 return -ENOMEM; 134 } 135 136 /* Power on PRU in case its not done as part of boot-loader */ 137 gdev->pruss_clk = clk_get(dev, "pruss"); 138 if (IS_ERR(gdev->pruss_clk)) { 139 dev_err(dev, "Failed to get clock\n"); 140 ret = PTR_ERR(gdev->pruss_clk); 141 kfree(gdev->info); 142 kfree(gdev); 143 return ret; 144 } else { 145 clk_enable(gdev->pruss_clk); 146 } 147 148 regs_prussio = platform_get_resource(pdev, IORESOURCE_MEM, 0); 149 if (!regs_prussio) { 150 dev_err(dev, "No PRUSS I/O resource specified\n"); 151 goto out_free; 152 } 153 154 if (!regs_prussio->start) { 155 dev_err(dev, "Invalid memory resource\n"); 156 goto out_free; 157 } 158 159 if (pdata->sram_pool) { 160 gdev->sram_pool = pdata->sram_pool; 161 gdev->sram_vaddr = 162 (unsigned long)gen_pool_dma_alloc(gdev->sram_pool, 163 sram_pool_sz, &gdev->sram_paddr); 164 if (!gdev->sram_vaddr) { 165 dev_err(dev, "Could not allocate SRAM pool\n"); 166 goto out_free; 167 } 168 } 169 170 gdev->ddr_vaddr = dma_alloc_coherent(dev, extram_pool_sz, 171 &(gdev->ddr_paddr), GFP_KERNEL | GFP_DMA); 172 if (!gdev->ddr_vaddr) { 173 dev_err(dev, "Could not allocate external memory\n"); 174 goto out_free; 175 } 176 177 len = resource_size(regs_prussio); 178 gdev->prussio_vaddr = ioremap(regs_prussio->start, len); 179 if (!gdev->prussio_vaddr) { 180 dev_err(dev, "Can't remap PRUSS I/O address range\n"); 181 goto out_free; 182 } 183 184 gdev->pintc_base = pdata->pintc_base; 185 gdev->hostirq_start = platform_get_irq(pdev, 0); 186 187 for (cnt = 0, p = gdev->info; cnt < MAX_PRUSS_EVT; cnt++, p++) { 188 p->mem[0].addr = regs_prussio->start; 189 p->mem[0].size = resource_size(regs_prussio); 190 p->mem[0].memtype = UIO_MEM_PHYS; 191 192 p->mem[1].addr = gdev->sram_paddr; 193 p->mem[1].size = sram_pool_sz; 194 p->mem[1].memtype = UIO_MEM_PHYS; 195 196 p->mem[2].addr = gdev->ddr_paddr; 197 p->mem[2].size = extram_pool_sz; 198 p->mem[2].memtype = UIO_MEM_PHYS; 199 200 p->name = kasprintf(GFP_KERNEL, "pruss_evt%d", cnt); 201 p->version = DRV_VERSION; 202 203 /* Register PRUSS IRQ lines */ 204 p->irq = gdev->hostirq_start + cnt; 205 p->handler = pruss_handler; 206 p->priv = gdev; 207 208 ret = uio_register_device(dev, p); 209 if (ret < 0) 210 goto out_free; 211 } 212 213 platform_set_drvdata(pdev, gdev); 214 return 0; 215 216 out_free: 217 pruss_cleanup(dev, gdev); 218 return ret; 219 } 220 221 static int pruss_remove(struct platform_device *dev) 222 { 223 struct uio_pruss_dev *gdev = platform_get_drvdata(dev); 224 225 pruss_cleanup(&dev->dev, gdev); 226 return 0; 227 } 228 229 static struct platform_driver pruss_driver = { 230 .probe = pruss_probe, 231 .remove = pruss_remove, 232 .driver = { 233 .name = DRV_NAME, 234 }, 235 }; 236 237 module_platform_driver(pruss_driver); 238 239 MODULE_LICENSE("GPL v2"); 240 MODULE_VERSION(DRV_VERSION); 241 MODULE_AUTHOR("Amit Chatterjee <amit.chatterjee@ti.com>"); 242 MODULE_AUTHOR("Pratheesh Gangadhar <pratheesh@ti.com>"); 243