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/sizes.h> 28 #include <linux/slab.h> 29 #include <linux/genalloc.h> 30 31 #define DRV_NAME "pruss_uio" 32 #define DRV_VERSION "1.0" 33 34 static int sram_pool_sz = SZ_16K; 35 module_param(sram_pool_sz, int, 0); 36 MODULE_PARM_DESC(sram_pool_sz, "sram pool size to allocate "); 37 38 static int extram_pool_sz = SZ_256K; 39 module_param(extram_pool_sz, int, 0); 40 MODULE_PARM_DESC(extram_pool_sz, "external ram pool size to allocate"); 41 42 /* 43 * Host event IRQ numbers from PRUSS - PRUSS can generate up to 8 interrupt 44 * events to AINTC of ARM host processor - which can be used for IPC b/w PRUSS 45 * firmware and user space application, async notification from PRU firmware 46 * to user space application 47 * 3 PRU_EVTOUT0 48 * 4 PRU_EVTOUT1 49 * 5 PRU_EVTOUT2 50 * 6 PRU_EVTOUT3 51 * 7 PRU_EVTOUT4 52 * 8 PRU_EVTOUT5 53 * 9 PRU_EVTOUT6 54 * 10 PRU_EVTOUT7 55 */ 56 #define MAX_PRUSS_EVT 8 57 58 #define PINTC_HIDISR 0x0038 59 #define PINTC_HIPIR 0x0900 60 #define HIPIR_NOPEND 0x80000000 61 #define PINTC_HIER 0x1500 62 63 struct uio_pruss_dev { 64 struct uio_info *info; 65 struct clk *pruss_clk; 66 dma_addr_t sram_paddr; 67 dma_addr_t ddr_paddr; 68 void __iomem *prussio_vaddr; 69 unsigned long sram_vaddr; 70 void *ddr_vaddr; 71 unsigned int hostirq_start; 72 unsigned int pintc_base; 73 struct gen_pool *sram_pool; 74 }; 75 76 static irqreturn_t pruss_handler(int irq, struct uio_info *info) 77 { 78 struct uio_pruss_dev *gdev = info->priv; 79 int intr_bit = (irq - gdev->hostirq_start + 2); 80 int val, intr_mask = (1 << intr_bit); 81 void __iomem *base = gdev->prussio_vaddr + gdev->pintc_base; 82 void __iomem *intren_reg = base + PINTC_HIER; 83 void __iomem *intrdis_reg = base + PINTC_HIDISR; 84 void __iomem *intrstat_reg = base + PINTC_HIPIR + (intr_bit << 2); 85 86 val = ioread32(intren_reg); 87 /* Is interrupt enabled and active ? */ 88 if (!(val & intr_mask) && (ioread32(intrstat_reg) & HIPIR_NOPEND)) 89 return IRQ_NONE; 90 /* Disable interrupt */ 91 iowrite32(intr_bit, intrdis_reg); 92 return IRQ_HANDLED; 93 } 94 95 static void pruss_cleanup(struct device *dev, struct uio_pruss_dev *gdev) 96 { 97 int cnt; 98 struct uio_info *p = gdev->info; 99 100 for (cnt = 0; cnt < MAX_PRUSS_EVT; cnt++, p++) { 101 uio_unregister_device(p); 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 clk_disable(gdev->pruss_clk); 113 } 114 115 static int pruss_probe(struct platform_device *pdev) 116 { 117 struct uio_info *p; 118 struct uio_pruss_dev *gdev; 119 struct resource *regs_prussio; 120 struct device *dev = &pdev->dev; 121 int ret, cnt, i, len; 122 struct uio_pruss_pdata *pdata = dev_get_platdata(dev); 123 124 gdev = devm_kzalloc(dev, sizeof(struct uio_pruss_dev), GFP_KERNEL); 125 if (!gdev) 126 return -ENOMEM; 127 128 gdev->info = devm_kcalloc(dev, MAX_PRUSS_EVT, sizeof(*p), GFP_KERNEL); 129 if (!gdev->info) 130 return -ENOMEM; 131 132 /* Power on PRU in case its not done as part of boot-loader */ 133 gdev->pruss_clk = devm_clk_get(dev, "pruss"); 134 if (IS_ERR(gdev->pruss_clk)) { 135 dev_err(dev, "Failed to get clock\n"); 136 return PTR_ERR(gdev->pruss_clk); 137 } 138 139 ret = clk_enable(gdev->pruss_clk); 140 if (ret) { 141 dev_err(dev, "Failed to enable clock\n"); 142 return ret; 143 } 144 145 regs_prussio = platform_get_resource(pdev, IORESOURCE_MEM, 0); 146 if (!regs_prussio) { 147 dev_err(dev, "No PRUSS I/O resource specified\n"); 148 ret = -EIO; 149 goto err_clk_disable; 150 } 151 152 if (!regs_prussio->start) { 153 dev_err(dev, "Invalid memory resource\n"); 154 ret = -EIO; 155 goto err_clk_disable; 156 } 157 158 if (pdata->sram_pool) { 159 gdev->sram_pool = pdata->sram_pool; 160 gdev->sram_vaddr = 161 (unsigned long)gen_pool_dma_alloc(gdev->sram_pool, 162 sram_pool_sz, &gdev->sram_paddr); 163 if (!gdev->sram_vaddr) { 164 dev_err(dev, "Could not allocate SRAM pool\n"); 165 ret = -ENOMEM; 166 goto err_clk_disable; 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 ret = -ENOMEM; 175 goto err_free_sram; 176 } 177 178 len = resource_size(regs_prussio); 179 gdev->prussio_vaddr = ioremap(regs_prussio->start, len); 180 if (!gdev->prussio_vaddr) { 181 dev_err(dev, "Can't remap PRUSS I/O address range\n"); 182 ret = -ENOMEM; 183 goto err_free_ddr_vaddr; 184 } 185 186 gdev->pintc_base = pdata->pintc_base; 187 gdev->hostirq_start = platform_get_irq(pdev, 0); 188 189 for (cnt = 0, p = gdev->info; cnt < MAX_PRUSS_EVT; cnt++, p++) { 190 p->mem[0].addr = regs_prussio->start; 191 p->mem[0].size = resource_size(regs_prussio); 192 p->mem[0].memtype = UIO_MEM_PHYS; 193 194 p->mem[1].addr = gdev->sram_paddr; 195 p->mem[1].size = sram_pool_sz; 196 p->mem[1].memtype = UIO_MEM_PHYS; 197 198 p->mem[2].addr = gdev->ddr_paddr; 199 p->mem[2].size = extram_pool_sz; 200 p->mem[2].memtype = UIO_MEM_PHYS; 201 202 p->name = devm_kasprintf(dev, GFP_KERNEL, "pruss_evt%d", cnt); 203 p->version = DRV_VERSION; 204 205 /* Register PRUSS IRQ lines */ 206 p->irq = gdev->hostirq_start + cnt; 207 p->handler = pruss_handler; 208 p->priv = gdev; 209 210 ret = uio_register_device(dev, p); 211 if (ret < 0) 212 goto err_unloop; 213 } 214 215 platform_set_drvdata(pdev, gdev); 216 return 0; 217 218 err_unloop: 219 for (i = 0, p = gdev->info; i < cnt; i++, p++) { 220 uio_unregister_device(p); 221 } 222 iounmap(gdev->prussio_vaddr); 223 err_free_ddr_vaddr: 224 dma_free_coherent(dev, extram_pool_sz, gdev->ddr_vaddr, 225 gdev->ddr_paddr); 226 err_free_sram: 227 if (pdata->sram_pool) 228 gen_pool_free(gdev->sram_pool, gdev->sram_vaddr, sram_pool_sz); 229 err_clk_disable: 230 clk_disable(gdev->pruss_clk); 231 232 return ret; 233 } 234 235 static int pruss_remove(struct platform_device *dev) 236 { 237 struct uio_pruss_dev *gdev = platform_get_drvdata(dev); 238 239 pruss_cleanup(&dev->dev, gdev); 240 return 0; 241 } 242 243 static struct platform_driver pruss_driver = { 244 .probe = pruss_probe, 245 .remove = pruss_remove, 246 .driver = { 247 .name = DRV_NAME, 248 }, 249 }; 250 251 module_platform_driver(pruss_driver); 252 253 MODULE_LICENSE("GPL v2"); 254 MODULE_VERSION(DRV_VERSION); 255 MODULE_AUTHOR("Amit Chatterjee <amit.chatterjee@ti.com>"); 256 MODULE_AUTHOR("Pratheesh Gangadhar <pratheesh@ti.com>"); 257