1/* sun3x_esp.c: ESP front-end for Sun3x systems. 2 * 3 * Copyright (C) 2007,2008 Thomas Bogendoerfer (tsbogend@alpha.franken.de) 4 */ 5 6#include <linux/kernel.h> 7#include <linux/gfp.h> 8#include <linux/types.h> 9#include <linux/delay.h> 10#include <linux/module.h> 11#include <linux/init.h> 12#include <linux/platform_device.h> 13#include <linux/dma-mapping.h> 14#include <linux/interrupt.h> 15 16#include <asm/sun3x.h> 17#include <asm/io.h> 18#include <asm/dma.h> 19#include <asm/dvma.h> 20 21/* DMA controller reg offsets */ 22#define DMA_CSR 0x00UL /* rw DMA control/status register 0x00 */ 23#define DMA_ADDR 0x04UL /* rw DMA transfer address register 0x04 */ 24#define DMA_COUNT 0x08UL /* rw DMA transfer count register 0x08 */ 25#define DMA_TEST 0x0cUL /* rw DMA test/debug register 0x0c */ 26 27#include <scsi/scsi_host.h> 28 29#include "esp_scsi.h" 30 31#define DRV_MODULE_NAME "sun3x_esp" 32#define PFX DRV_MODULE_NAME ": " 33#define DRV_VERSION "1.000" 34#define DRV_MODULE_RELDATE "Nov 1, 2007" 35 36#define dma_read32(REG) \ 37 *(volatile u32 *)(esp->dma_regs + (REG)) 38#define dma_write32(VAL, REG) \ 39 do { *(volatile u32 *)(esp->dma_regs + (REG)) = (VAL); } while (0) 40 41static void sun3x_esp_write8(struct esp *esp, u8 val, unsigned long reg) 42{ 43 writeb(val, esp->regs + (reg * 4UL)); 44} 45 46static u8 sun3x_esp_read8(struct esp *esp, unsigned long reg) 47{ 48 return readb(esp->regs + (reg * 4UL)); 49} 50 51static dma_addr_t sun3x_esp_map_single(struct esp *esp, void *buf, 52 size_t sz, int dir) 53{ 54 return dma_map_single(esp->dev, buf, sz, dir); 55} 56 57static int sun3x_esp_map_sg(struct esp *esp, struct scatterlist *sg, 58 int num_sg, int dir) 59{ 60 return dma_map_sg(esp->dev, sg, num_sg, dir); 61} 62 63static void sun3x_esp_unmap_single(struct esp *esp, dma_addr_t addr, 64 size_t sz, int dir) 65{ 66 dma_unmap_single(esp->dev, addr, sz, dir); 67} 68 69static void sun3x_esp_unmap_sg(struct esp *esp, struct scatterlist *sg, 70 int num_sg, int dir) 71{ 72 dma_unmap_sg(esp->dev, sg, num_sg, dir); 73} 74 75static int sun3x_esp_irq_pending(struct esp *esp) 76{ 77 if (dma_read32(DMA_CSR) & (DMA_HNDL_INTR | DMA_HNDL_ERROR)) 78 return 1; 79 return 0; 80} 81 82static void sun3x_esp_reset_dma(struct esp *esp) 83{ 84 u32 val; 85 86 val = dma_read32(DMA_CSR); 87 dma_write32(val | DMA_RST_SCSI, DMA_CSR); 88 dma_write32(val & ~DMA_RST_SCSI, DMA_CSR); 89 90 /* Enable interrupts. */ 91 val = dma_read32(DMA_CSR); 92 dma_write32(val | DMA_INT_ENAB, DMA_CSR); 93} 94 95static void sun3x_esp_dma_drain(struct esp *esp) 96{ 97 u32 csr; 98 int lim; 99 100 csr = dma_read32(DMA_CSR); 101 if (!(csr & DMA_FIFO_ISDRAIN)) 102 return; 103 104 dma_write32(csr | DMA_FIFO_STDRAIN, DMA_CSR); 105 106 lim = 1000; 107 while (dma_read32(DMA_CSR) & DMA_FIFO_ISDRAIN) { 108 if (--lim == 0) { 109 printk(KERN_ALERT PFX "esp%d: DMA will not drain!\n", 110 esp->host->unique_id); 111 break; 112 } 113 udelay(1); 114 } 115} 116 117static void sun3x_esp_dma_invalidate(struct esp *esp) 118{ 119 u32 val; 120 int lim; 121 122 lim = 1000; 123 while ((val = dma_read32(DMA_CSR)) & DMA_PEND_READ) { 124 if (--lim == 0) { 125 printk(KERN_ALERT PFX "esp%d: DMA will not " 126 "invalidate!\n", esp->host->unique_id); 127 break; 128 } 129 udelay(1); 130 } 131 132 val &= ~(DMA_ENABLE | DMA_ST_WRITE | DMA_BCNT_ENAB); 133 val |= DMA_FIFO_INV; 134 dma_write32(val, DMA_CSR); 135 val &= ~DMA_FIFO_INV; 136 dma_write32(val, DMA_CSR); 137} 138 139static void sun3x_esp_send_dma_cmd(struct esp *esp, u32 addr, u32 esp_count, 140 u32 dma_count, int write, u8 cmd) 141{ 142 u32 csr; 143 144 BUG_ON(!(cmd & ESP_CMD_DMA)); 145 146 sun3x_esp_write8(esp, (esp_count >> 0) & 0xff, ESP_TCLOW); 147 sun3x_esp_write8(esp, (esp_count >> 8) & 0xff, ESP_TCMED); 148 csr = dma_read32(DMA_CSR); 149 csr |= DMA_ENABLE; 150 if (write) 151 csr |= DMA_ST_WRITE; 152 else 153 csr &= ~DMA_ST_WRITE; 154 dma_write32(csr, DMA_CSR); 155 dma_write32(addr, DMA_ADDR); 156 157 scsi_esp_cmd(esp, cmd); 158} 159 160static int sun3x_esp_dma_error(struct esp *esp) 161{ 162 u32 csr = dma_read32(DMA_CSR); 163 164 if (csr & DMA_HNDL_ERROR) 165 return 1; 166 167 return 0; 168} 169 170static const struct esp_driver_ops sun3x_esp_ops = { 171 .esp_write8 = sun3x_esp_write8, 172 .esp_read8 = sun3x_esp_read8, 173 .map_single = sun3x_esp_map_single, 174 .map_sg = sun3x_esp_map_sg, 175 .unmap_single = sun3x_esp_unmap_single, 176 .unmap_sg = sun3x_esp_unmap_sg, 177 .irq_pending = sun3x_esp_irq_pending, 178 .reset_dma = sun3x_esp_reset_dma, 179 .dma_drain = sun3x_esp_dma_drain, 180 .dma_invalidate = sun3x_esp_dma_invalidate, 181 .send_dma_cmd = sun3x_esp_send_dma_cmd, 182 .dma_error = sun3x_esp_dma_error, 183}; 184 185static int __devinit esp_sun3x_probe(struct platform_device *dev) 186{ 187 struct scsi_host_template *tpnt = &scsi_esp_template; 188 struct Scsi_Host *host; 189 struct esp *esp; 190 struct resource *res; 191 int err = -ENOMEM; 192 193 host = scsi_host_alloc(tpnt, sizeof(struct esp)); 194 if (!host) 195 goto fail; 196 197 host->max_id = 8; 198 esp = shost_priv(host); 199 200 esp->host = host; 201 esp->dev = dev; 202 esp->ops = &sun3x_esp_ops; 203 204 res = platform_get_resource(dev, IORESOURCE_MEM, 0); 205 if (!res || !res->start) 206 goto fail_unlink; 207 208 esp->regs = ioremap_nocache(res->start, 0x20); 209 if (!esp->regs) 210 goto fail_unmap_regs; 211 212 res = platform_get_resource(dev, IORESOURCE_MEM, 1); 213 if (!res || !res->start) 214 goto fail_unmap_regs; 215 216 esp->dma_regs = ioremap_nocache(res->start, 0x10); 217 218 esp->command_block = dma_alloc_coherent(esp->dev, 16, 219 &esp->command_block_dma, 220 GFP_KERNEL); 221 if (!esp->command_block) 222 goto fail_unmap_regs_dma; 223 224 host->irq = platform_get_irq(dev, 0); 225 err = request_irq(host->irq, scsi_esp_intr, IRQF_SHARED, 226 "SUN3X ESP", esp); 227 if (err < 0) 228 goto fail_unmap_command_block; 229 230 esp->scsi_id = 7; 231 esp->host->this_id = esp->scsi_id; 232 esp->scsi_id_mask = (1 << esp->scsi_id); 233 esp->cfreq = 20000000; 234 235 dev_set_drvdata(&dev->dev, esp); 236 237 err = scsi_esp_register(esp, &dev->dev); 238 if (err) 239 goto fail_free_irq; 240 241 return 0; 242 243fail_free_irq: 244 free_irq(host->irq, esp); 245fail_unmap_command_block: 246 dma_free_coherent(esp->dev, 16, 247 esp->command_block, 248 esp->command_block_dma); 249fail_unmap_regs_dma: 250 iounmap(esp->dma_regs); 251fail_unmap_regs: 252 iounmap(esp->regs); 253fail_unlink: 254 scsi_host_put(host); 255fail: 256 return err; 257} 258 259static int __devexit esp_sun3x_remove(struct platform_device *dev) 260{ 261 struct esp *esp = dev_get_drvdata(&dev->dev); 262 unsigned int irq = esp->host->irq; 263 u32 val; 264 265 scsi_esp_unregister(esp); 266 267 /* Disable interrupts. */ 268 val = dma_read32(DMA_CSR); 269 dma_write32(val & ~DMA_INT_ENAB, DMA_CSR); 270 271 free_irq(irq, esp); 272 dma_free_coherent(esp->dev, 16, 273 esp->command_block, 274 esp->command_block_dma); 275 276 scsi_host_put(esp->host); 277 278 return 0; 279} 280 281static struct platform_driver esp_sun3x_driver = { 282 .probe = esp_sun3x_probe, 283 .remove = __devexit_p(esp_sun3x_remove), 284 .driver = { 285 .name = "sun3x_esp", 286 .owner = THIS_MODULE, 287 }, 288}; 289 290static int __init sun3x_esp_init(void) 291{ 292 return platform_driver_register(&esp_sun3x_driver); 293} 294 295static void __exit sun3x_esp_exit(void) 296{ 297 platform_driver_unregister(&esp_sun3x_driver); 298} 299 300MODULE_DESCRIPTION("Sun3x ESP SCSI driver"); 301MODULE_AUTHOR("Thomas Bogendoerfer (tsbogend@alpha.franken.de)"); 302MODULE_LICENSE("GPL"); 303MODULE_VERSION(DRV_VERSION); 304 305module_init(sun3x_esp_init); 306module_exit(sun3x_esp_exit); 307MODULE_ALIAS("platform:sun3x_esp"); 308