1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Programmable Real-Time Unit Sub System (PRUSS) UIO driver (uio_pruss) 4 * 5 * This driver exports PRUSS host event out interrupts and PRUSS, L3 RAM, 6 * and DDR RAM to user space for applications interacting with PRUSS firmware 7 * 8 * Copyright (C) 2010-11 Texas Instruments Incorporated - http://www.ti.com/ 9 */ 10 #include <linux/device.h> 11 #include <linux/module.h> 12 #include <linux/moduleparam.h> 13 #include <linux/platform_device.h> 14 #include <linux/uio_driver.h> 15 #include <linux/platform_data/uio_pruss.h> 16 #include <linux/io.h> 17 #include <linux/clk.h> 18 #include <linux/dma-mapping.h> 19 #include <linux/sizes.h> 20 #include <linux/slab.h> 21 #include <linux/genalloc.h> 22 23 #define DRV_NAME "pruss_uio" 24 #define DRV_VERSION "1.0" 25 26 static int sram_pool_sz = SZ_16K; 27 module_param(sram_pool_sz, int, 0); 28 MODULE_PARM_DESC(sram_pool_sz, "sram pool size to allocate "); 29 30 static int extram_pool_sz = SZ_256K; 31 module_param(extram_pool_sz, int, 0); 32 MODULE_PARM_DESC(extram_pool_sz, "external ram pool size to allocate"); 33 34 /* 35 * Host event IRQ numbers from PRUSS - PRUSS can generate up to 8 interrupt 36 * events to AINTC of ARM host processor - which can be used for IPC b/w PRUSS 37 * firmware and user space application, async notification from PRU firmware 38 * to user space application 39 * 3 PRU_EVTOUT0 40 * 4 PRU_EVTOUT1 41 * 5 PRU_EVTOUT2 42 * 6 PRU_EVTOUT3 43 * 7 PRU_EVTOUT4 44 * 8 PRU_EVTOUT5 45 * 9 PRU_EVTOUT6 46 * 10 PRU_EVTOUT7 47 */ 48 #define MAX_PRUSS_EVT 8 49 50 #define PINTC_HIDISR 0x0038 51 #define PINTC_HIPIR 0x0900 52 #define HIPIR_NOPEND 0x80000000 53 #define PINTC_HIER 0x1500 54 55 struct uio_pruss_dev { 56 struct uio_info *info; 57 struct clk *pruss_clk; 58 dma_addr_t sram_paddr; 59 dma_addr_t ddr_paddr; 60 void __iomem *prussio_vaddr; 61 unsigned long sram_vaddr; 62 void *ddr_vaddr; 63 unsigned int hostirq_start; 64 unsigned int pintc_base; 65 struct gen_pool *sram_pool; 66 }; 67 68 static irqreturn_t pruss_handler(int irq, struct uio_info *info) 69 { 70 struct uio_pruss_dev *gdev = info->priv; 71 int intr_bit = (irq - gdev->hostirq_start + 2); 72 int val, intr_mask = (1 << intr_bit); 73 void __iomem *base = gdev->prussio_vaddr + gdev->pintc_base; 74 void __iomem *intren_reg = base + PINTC_HIER; 75 void __iomem *intrdis_reg = base + PINTC_HIDISR; 76 void __iomem *intrstat_reg = base + PINTC_HIPIR + (intr_bit << 2); 77 78 val = ioread32(intren_reg); 79 /* Is interrupt enabled and active ? */ 80 if (!(val & intr_mask) && (ioread32(intrstat_reg) & HIPIR_NOPEND)) 81 return IRQ_NONE; 82 /* Disable interrupt */ 83 iowrite32(intr_bit, intrdis_reg); 84 return IRQ_HANDLED; 85 } 86 87 static void pruss_cleanup(struct device *dev, struct uio_pruss_dev *gdev) 88 { 89 int cnt; 90 struct uio_info *p = gdev->info; 91 92 for (cnt = 0; cnt < MAX_PRUSS_EVT; cnt++, p++) { 93 uio_unregister_device(p); 94 } 95 iounmap(gdev->prussio_vaddr); 96 if (gdev->ddr_vaddr) { 97 dma_free_coherent(dev, extram_pool_sz, gdev->ddr_vaddr, 98 gdev->ddr_paddr); 99 } 100 if (gdev->sram_vaddr) 101 gen_pool_free(gdev->sram_pool, 102 gdev->sram_vaddr, 103 sram_pool_sz); 104 clk_disable(gdev->pruss_clk); 105 } 106 107 static int pruss_probe(struct platform_device *pdev) 108 { 109 struct uio_info *p; 110 struct uio_pruss_dev *gdev; 111 struct resource *regs_prussio; 112 struct device *dev = &pdev->dev; 113 int ret, cnt, i, len; 114 struct uio_pruss_pdata *pdata = dev_get_platdata(dev); 115 116 gdev = devm_kzalloc(dev, sizeof(struct uio_pruss_dev), GFP_KERNEL); 117 if (!gdev) 118 return -ENOMEM; 119 120 gdev->info = devm_kcalloc(dev, MAX_PRUSS_EVT, sizeof(*p), GFP_KERNEL); 121 if (!gdev->info) 122 return -ENOMEM; 123 124 /* Power on PRU in case its not done as part of boot-loader */ 125 gdev->pruss_clk = devm_clk_get(dev, "pruss"); 126 if (IS_ERR(gdev->pruss_clk)) { 127 dev_err(dev, "Failed to get clock\n"); 128 return PTR_ERR(gdev->pruss_clk); 129 } 130 131 ret = clk_enable(gdev->pruss_clk); 132 if (ret) { 133 dev_err(dev, "Failed to enable clock\n"); 134 return ret; 135 } 136 137 regs_prussio = platform_get_resource(pdev, IORESOURCE_MEM, 0); 138 if (!regs_prussio) { 139 dev_err(dev, "No PRUSS I/O resource specified\n"); 140 ret = -EIO; 141 goto err_clk_disable; 142 } 143 144 if (!regs_prussio->start) { 145 dev_err(dev, "Invalid memory resource\n"); 146 ret = -EIO; 147 goto err_clk_disable; 148 } 149 150 if (pdata->sram_pool) { 151 gdev->sram_pool = pdata->sram_pool; 152 gdev->sram_vaddr = 153 (unsigned long)gen_pool_dma_alloc(gdev->sram_pool, 154 sram_pool_sz, &gdev->sram_paddr); 155 if (!gdev->sram_vaddr) { 156 dev_err(dev, "Could not allocate SRAM pool\n"); 157 ret = -ENOMEM; 158 goto err_clk_disable; 159 } 160 } 161 162 gdev->ddr_vaddr = dma_alloc_coherent(dev, extram_pool_sz, 163 &(gdev->ddr_paddr), GFP_KERNEL | GFP_DMA); 164 if (!gdev->ddr_vaddr) { 165 dev_err(dev, "Could not allocate external memory\n"); 166 ret = -ENOMEM; 167 goto err_free_sram; 168 } 169 170 len = resource_size(regs_prussio); 171 gdev->prussio_vaddr = ioremap(regs_prussio->start, len); 172 if (!gdev->prussio_vaddr) { 173 dev_err(dev, "Can't remap PRUSS I/O address range\n"); 174 ret = -ENOMEM; 175 goto err_free_ddr_vaddr; 176 } 177 178 ret = platform_get_irq(pdev, 0); 179 if (ret < 0) 180 goto err_unmap; 181 182 gdev->hostirq_start = ret; 183 gdev->pintc_base = pdata->pintc_base; 184 185 for (cnt = 0, p = gdev->info; cnt < MAX_PRUSS_EVT; cnt++, p++) { 186 p->mem[0].addr = regs_prussio->start; 187 p->mem[0].size = resource_size(regs_prussio); 188 p->mem[0].memtype = UIO_MEM_PHYS; 189 190 p->mem[1].addr = gdev->sram_paddr; 191 p->mem[1].size = sram_pool_sz; 192 p->mem[1].memtype = UIO_MEM_PHYS; 193 194 p->mem[2].addr = gdev->ddr_paddr; 195 p->mem[2].size = extram_pool_sz; 196 p->mem[2].memtype = UIO_MEM_PHYS; 197 198 p->name = devm_kasprintf(dev, GFP_KERNEL, "pruss_evt%d", cnt); 199 p->version = DRV_VERSION; 200 201 /* Register PRUSS IRQ lines */ 202 p->irq = gdev->hostirq_start + cnt; 203 p->handler = pruss_handler; 204 p->priv = gdev; 205 206 ret = uio_register_device(dev, p); 207 if (ret < 0) 208 goto err_unloop; 209 } 210 211 platform_set_drvdata(pdev, gdev); 212 return 0; 213 214 err_unloop: 215 for (i = 0, p = gdev->info; i < cnt; i++, p++) { 216 uio_unregister_device(p); 217 } 218 err_unmap: 219 iounmap(gdev->prussio_vaddr); 220 err_free_ddr_vaddr: 221 dma_free_coherent(dev, extram_pool_sz, gdev->ddr_vaddr, 222 gdev->ddr_paddr); 223 err_free_sram: 224 if (pdata->sram_pool) 225 gen_pool_free(gdev->sram_pool, gdev->sram_vaddr, sram_pool_sz); 226 err_clk_disable: 227 clk_disable(gdev->pruss_clk); 228 229 return ret; 230 } 231 232 static int pruss_remove(struct platform_device *dev) 233 { 234 struct uio_pruss_dev *gdev = platform_get_drvdata(dev); 235 236 pruss_cleanup(&dev->dev, gdev); 237 return 0; 238 } 239 240 static struct platform_driver pruss_driver = { 241 .probe = pruss_probe, 242 .remove = pruss_remove, 243 .driver = { 244 .name = DRV_NAME, 245 }, 246 }; 247 248 module_platform_driver(pruss_driver); 249 250 MODULE_LICENSE("GPL v2"); 251 MODULE_VERSION(DRV_VERSION); 252 MODULE_AUTHOR("Amit Chatterjee <amit.chatterjee@ti.com>"); 253 MODULE_AUTHOR("Pratheesh Gangadhar <pratheesh@ti.com>"); 254