1 /* 2 * This file is subject to the terms and conditions of the GNU General Public 3 * License. See the file "COPYING" in the main directory of this archive 4 * for more details. 5 * 6 * Copyright (C) 1996 David S. Miller (davem@davemloft.net) 7 * Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu) 8 * Copyright (C) 2001 Florian Lohoff (flo@rfc822.org) 9 * Copyright (C) 2003, 07 Ralf Baechle (ralf@linux-mips.org) 10 * 11 * (In all truth, Jed Schimmel wrote all this code.) 12 */ 13 14 #undef DEBUG 15 16 #include <linux/delay.h> 17 #include <linux/dma-mapping.h> 18 #include <linux/gfp.h> 19 #include <linux/interrupt.h> 20 #include <linux/init.h> 21 #include <linux/kernel.h> 22 #include <linux/types.h> 23 #include <linux/module.h> 24 #include <linux/platform_device.h> 25 #include <linux/spinlock.h> 26 27 #include <asm/sgi/hpc3.h> 28 #include <asm/sgi/ip22.h> 29 #include <asm/sgi/wd.h> 30 31 #include "scsi.h" 32 #include "wd33c93.h" 33 34 struct ip22_hostdata { 35 struct WD33C93_hostdata wh; 36 dma_addr_t dma; 37 void *cpu; 38 struct device *dev; 39 }; 40 41 #define host_to_hostdata(host) ((struct ip22_hostdata *)((host)->hostdata)) 42 43 struct hpc_chunk { 44 struct hpc_dma_desc desc; 45 u32 _padding; /* align to quadword boundary */ 46 }; 47 48 /* space for hpc dma descriptors */ 49 #define HPC_DMA_SIZE PAGE_SIZE 50 51 #define DMA_DIR(d) ((d == DATA_OUT_DIR) ? DMA_TO_DEVICE : DMA_FROM_DEVICE) 52 53 static irqreturn_t sgiwd93_intr(int irq, void *dev_id) 54 { 55 struct Scsi_Host * host = dev_id; 56 unsigned long flags; 57 58 spin_lock_irqsave(host->host_lock, flags); 59 wd33c93_intr(host); 60 spin_unlock_irqrestore(host->host_lock, flags); 61 62 return IRQ_HANDLED; 63 } 64 65 static inline 66 void fill_hpc_entries(struct ip22_hostdata *hd, struct scsi_cmnd *cmd, int din) 67 { 68 unsigned long len = cmd->SCp.this_residual; 69 void *addr = cmd->SCp.ptr; 70 dma_addr_t physaddr; 71 unsigned long count; 72 struct hpc_chunk *hcp; 73 74 physaddr = dma_map_single(hd->dev, addr, len, DMA_DIR(din)); 75 cmd->SCp.dma_handle = physaddr; 76 hcp = hd->cpu; 77 78 while (len) { 79 /* 80 * even cntinfo could be up to 16383, without 81 * magic only 8192 works correctly 82 */ 83 count = len > 8192 ? 8192 : len; 84 hcp->desc.pbuf = physaddr; 85 hcp->desc.cntinfo = count; 86 hcp++; 87 len -= count; 88 physaddr += count; 89 } 90 91 /* 92 * To make sure, if we trip an HPC bug, that we transfer every single 93 * byte, we tag on an extra zero length dma descriptor at the end of 94 * the chain. 95 */ 96 hcp->desc.pbuf = 0; 97 hcp->desc.cntinfo = HPCDMA_EOX; 98 dma_sync_single_for_device(hd->dev, hd->dma, 99 (unsigned long)(hcp + 1) - (unsigned long)hd->cpu, 100 DMA_TO_DEVICE); 101 } 102 103 static int dma_setup(struct scsi_cmnd *cmd, int datainp) 104 { 105 struct ip22_hostdata *hdata = host_to_hostdata(cmd->device->host); 106 struct hpc3_scsiregs *hregs = 107 (struct hpc3_scsiregs *) cmd->device->host->base; 108 109 pr_debug("dma_setup: datainp<%d> hcp<%p> ", datainp, hdata->cpu); 110 111 hdata->wh.dma_dir = datainp; 112 113 /* 114 * wd33c93 shouldn't pass us bogus dma_setups, but it does:-( The 115 * other wd33c93 drivers deal with it the same way (which isn't that 116 * obvious). IMHO a better fix would be, not to do these dma setups 117 * in the first place. 118 */ 119 if (cmd->SCp.ptr == NULL || cmd->SCp.this_residual == 0) 120 return 1; 121 122 fill_hpc_entries(hdata, cmd, datainp); 123 124 pr_debug(" HPCGO\n"); 125 126 /* Start up the HPC. */ 127 hregs->ndptr = hdata->dma; 128 if (datainp) 129 hregs->ctrl = HPC3_SCTRL_ACTIVE; 130 else 131 hregs->ctrl = HPC3_SCTRL_ACTIVE | HPC3_SCTRL_DIR; 132 133 return 0; 134 } 135 136 static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt, 137 int status) 138 { 139 struct ip22_hostdata *hdata = host_to_hostdata(instance); 140 struct hpc3_scsiregs *hregs; 141 142 if (!SCpnt) 143 return; 144 145 if (SCpnt->SCp.ptr == NULL || SCpnt->SCp.this_residual == 0) 146 return; 147 148 hregs = (struct hpc3_scsiregs *) SCpnt->device->host->base; 149 150 pr_debug("dma_stop: status<%d> ", status); 151 152 /* First stop the HPC and flush it's FIFO. */ 153 if (hdata->wh.dma_dir) { 154 hregs->ctrl |= HPC3_SCTRL_FLUSH; 155 while (hregs->ctrl & HPC3_SCTRL_ACTIVE) 156 barrier(); 157 } 158 hregs->ctrl = 0; 159 dma_unmap_single(hdata->dev, SCpnt->SCp.dma_handle, 160 SCpnt->SCp.this_residual, 161 DMA_DIR(hdata->wh.dma_dir)); 162 163 pr_debug("\n"); 164 } 165 166 void sgiwd93_reset(unsigned long base) 167 { 168 struct hpc3_scsiregs *hregs = (struct hpc3_scsiregs *) base; 169 170 hregs->ctrl = HPC3_SCTRL_CRESET; 171 udelay(50); 172 hregs->ctrl = 0; 173 } 174 EXPORT_SYMBOL_GPL(sgiwd93_reset); 175 176 static inline void init_hpc_chain(struct ip22_hostdata *hdata) 177 { 178 struct hpc_chunk *hcp = (struct hpc_chunk *)hdata->cpu; 179 dma_addr_t dma = hdata->dma; 180 unsigned long start, end; 181 182 start = (unsigned long) hcp; 183 end = start + HPC_DMA_SIZE; 184 while (start < end) { 185 hcp->desc.pnext = (u32) (dma + sizeof(struct hpc_chunk)); 186 hcp->desc.cntinfo = HPCDMA_EOX; 187 hcp++; 188 dma += sizeof(struct hpc_chunk); 189 start += sizeof(struct hpc_chunk); 190 } 191 hcp--; 192 hcp->desc.pnext = hdata->dma; 193 } 194 195 /* 196 * Kludge alert - the SCSI code calls the abort and reset method with int 197 * arguments not with pointers. So this is going to blow up beautyfully 198 * on 64-bit systems with memory outside the compat address spaces. 199 */ 200 static struct scsi_host_template sgiwd93_template = { 201 .module = THIS_MODULE, 202 .proc_name = "SGIWD93", 203 .name = "SGI WD93", 204 .queuecommand = wd33c93_queuecommand, 205 .eh_abort_handler = wd33c93_abort, 206 .eh_host_reset_handler = wd33c93_host_reset, 207 .can_queue = 16, 208 .this_id = 7, 209 .sg_tablesize = SG_ALL, 210 .cmd_per_lun = 8, 211 .dma_boundary = PAGE_SIZE - 1, 212 }; 213 214 static int sgiwd93_probe(struct platform_device *pdev) 215 { 216 struct sgiwd93_platform_data *pd = pdev->dev.platform_data; 217 unsigned char *wdregs = pd->wdregs; 218 struct hpc3_scsiregs *hregs = pd->hregs; 219 struct ip22_hostdata *hdata; 220 struct Scsi_Host *host; 221 wd33c93_regs regs; 222 unsigned int unit = pd->unit; 223 unsigned int irq = pd->irq; 224 int err; 225 226 host = scsi_host_alloc(&sgiwd93_template, sizeof(struct ip22_hostdata)); 227 if (!host) { 228 err = -ENOMEM; 229 goto out; 230 } 231 232 host->base = (unsigned long) hregs; 233 host->irq = irq; 234 235 hdata = host_to_hostdata(host); 236 hdata->dev = &pdev->dev; 237 hdata->cpu = dma_alloc_noncoherent(&pdev->dev, HPC_DMA_SIZE, 238 &hdata->dma, DMA_TO_DEVICE, GFP_KERNEL); 239 if (!hdata->cpu) { 240 printk(KERN_WARNING "sgiwd93: Could not allocate memory for " 241 "host %d buffer.\n", unit); 242 err = -ENOMEM; 243 goto out_put; 244 } 245 246 init_hpc_chain(hdata); 247 248 regs.SASR = wdregs + 3; 249 regs.SCMD = wdregs + 7; 250 251 hdata->wh.no_sync = 0; 252 hdata->wh.fast = 1; 253 hdata->wh.dma_mode = CTRL_BURST; 254 255 wd33c93_init(host, regs, dma_setup, dma_stop, WD33C93_FS_MHZ(20)); 256 257 err = request_irq(irq, sgiwd93_intr, 0, "SGI WD93", host); 258 if (err) { 259 printk(KERN_WARNING "sgiwd93: Could not register irq %d " 260 "for host %d.\n", irq, unit); 261 goto out_free; 262 } 263 264 platform_set_drvdata(pdev, host); 265 266 err = scsi_add_host(host, NULL); 267 if (err) 268 goto out_irq; 269 270 scsi_scan_host(host); 271 272 return 0; 273 274 out_irq: 275 free_irq(irq, host); 276 out_free: 277 dma_free_noncoherent(&pdev->dev, HPC_DMA_SIZE, hdata->cpu, hdata->dma, 278 DMA_TO_DEVICE); 279 out_put: 280 scsi_host_put(host); 281 out: 282 283 return err; 284 } 285 286 static int sgiwd93_remove(struct platform_device *pdev) 287 { 288 struct Scsi_Host *host = platform_get_drvdata(pdev); 289 struct ip22_hostdata *hdata = (struct ip22_hostdata *) host->hostdata; 290 struct sgiwd93_platform_data *pd = pdev->dev.platform_data; 291 292 scsi_remove_host(host); 293 free_irq(pd->irq, host); 294 dma_free_noncoherent(&pdev->dev, HPC_DMA_SIZE, hdata->cpu, hdata->dma, 295 DMA_TO_DEVICE); 296 scsi_host_put(host); 297 return 0; 298 } 299 300 static struct platform_driver sgiwd93_driver = { 301 .probe = sgiwd93_probe, 302 .remove = sgiwd93_remove, 303 .driver = { 304 .name = "sgiwd93", 305 } 306 }; 307 308 static int __init sgiwd93_module_init(void) 309 { 310 return platform_driver_register(&sgiwd93_driver); 311 } 312 313 static void __exit sgiwd93_module_exit(void) 314 { 315 return platform_driver_unregister(&sgiwd93_driver); 316 } 317 318 module_init(sgiwd93_module_init); 319 module_exit(sgiwd93_module_exit); 320 321 MODULE_DESCRIPTION("SGI WD33C93 driver"); 322 MODULE_AUTHOR("Ralf Baechle <ralf@linux-mips.org>"); 323 MODULE_LICENSE("GPL"); 324 MODULE_ALIAS("platform:sgiwd93"); 325