/* sun3x_esp.c: ESP front-end for Sun3x systems. * * Copyright (C) 2007,2008 Thomas Bogendoerfer (tsbogend@alpha.franken.de) */ #include <linux/kernel.h> #include <linux/types.h> #include <linux/delay.h> #include <linux/module.h> #include <linux/init.h> #include <linux/platform_device.h> #include <linux/dma-mapping.h> #include <linux/interrupt.h> #include <asm/sun3x.h> #include <asm/io.h> #include <asm/dma.h> #include <asm/dvma.h> /* DMA controller reg offsets */ #define DMA_CSR 0x00UL /* rw DMA control/status register 0x00 */ #define DMA_ADDR 0x04UL /* rw DMA transfer address register 0x04 */ #define DMA_COUNT 0x08UL /* rw DMA transfer count register 0x08 */ #define DMA_TEST 0x0cUL /* rw DMA test/debug register 0x0c */ #include <scsi/scsi_host.h> #include "esp_scsi.h" #define DRV_MODULE_NAME "sun3x_esp" #define PFX DRV_MODULE_NAME ": " #define DRV_VERSION "1.000" #define DRV_MODULE_RELDATE "Nov 1, 2007" /* * m68k always assumes readl/writel operate on little endian * mmio space; this is wrong at least for Sun3x, so we * need to workaround this until a proper way is found */ #if 0 #define dma_read32(REG) \ readl(esp->dma_regs + (REG)) #define dma_write32(VAL, REG) \ writel((VAL), esp->dma_regs + (REG)) #else #define dma_read32(REG) \ *(volatile u32 *)(esp->dma_regs + (REG)) #define dma_write32(VAL, REG) \ do { *(volatile u32 *)(esp->dma_regs + (REG)) = (VAL); } while (0) #endif static void sun3x_esp_write8(struct esp *esp, u8 val, unsigned long reg) { writeb(val, esp->regs + (reg * 4UL)); } static u8 sun3x_esp_read8(struct esp *esp, unsigned long reg) { return readb(esp->regs + (reg * 4UL)); } static dma_addr_t sun3x_esp_map_single(struct esp *esp, void *buf, size_t sz, int dir) { return dma_map_single(esp->dev, buf, sz, dir); } static int sun3x_esp_map_sg(struct esp *esp, struct scatterlist *sg, int num_sg, int dir) { return dma_map_sg(esp->dev, sg, num_sg, dir); } static void sun3x_esp_unmap_single(struct esp *esp, dma_addr_t addr, size_t sz, int dir) { dma_unmap_single(esp->dev, addr, sz, dir); } static void sun3x_esp_unmap_sg(struct esp *esp, struct scatterlist *sg, int num_sg, int dir) { dma_unmap_sg(esp->dev, sg, num_sg, dir); } static int sun3x_esp_irq_pending(struct esp *esp) { if (dma_read32(DMA_CSR) & (DMA_HNDL_INTR | DMA_HNDL_ERROR)) return 1; return 0; } static void sun3x_esp_reset_dma(struct esp *esp) { u32 val; val = dma_read32(DMA_CSR); dma_write32(val | DMA_RST_SCSI, DMA_CSR); dma_write32(val & ~DMA_RST_SCSI, DMA_CSR); /* Enable interrupts. */ val = dma_read32(DMA_CSR); dma_write32(val | DMA_INT_ENAB, DMA_CSR); } static void sun3x_esp_dma_drain(struct esp *esp) { u32 csr; int lim; csr = dma_read32(DMA_CSR); if (!(csr & DMA_FIFO_ISDRAIN)) return; dma_write32(csr | DMA_FIFO_STDRAIN, DMA_CSR); lim = 1000; while (dma_read32(DMA_CSR) & DMA_FIFO_ISDRAIN) { if (--lim == 0) { printk(KERN_ALERT PFX "esp%d: DMA will not drain!\n", esp->host->unique_id); break; } udelay(1); } } static void sun3x_esp_dma_invalidate(struct esp *esp) { u32 val; int lim; lim = 1000; while ((val = dma_read32(DMA_CSR)) & DMA_PEND_READ) { if (--lim == 0) { printk(KERN_ALERT PFX "esp%d: DMA will not " "invalidate!\n", esp->host->unique_id); break; } udelay(1); } val &= ~(DMA_ENABLE | DMA_ST_WRITE | DMA_BCNT_ENAB); val |= DMA_FIFO_INV; dma_write32(val, DMA_CSR); val &= ~DMA_FIFO_INV; dma_write32(val, DMA_CSR); } static void sun3x_esp_send_dma_cmd(struct esp *esp, u32 addr, u32 esp_count, u32 dma_count, int write, u8 cmd) { u32 csr; BUG_ON(!(cmd & ESP_CMD_DMA)); sun3x_esp_write8(esp, (esp_count >> 0) & 0xff, ESP_TCLOW); sun3x_esp_write8(esp, (esp_count >> 8) & 0xff, ESP_TCMED); csr = dma_read32(DMA_CSR); csr |= DMA_ENABLE; if (write) csr |= DMA_ST_WRITE; else csr &= ~DMA_ST_WRITE; dma_write32(csr, DMA_CSR); dma_write32(addr, DMA_ADDR); scsi_esp_cmd(esp, cmd); } static int sun3x_esp_dma_error(struct esp *esp) { u32 csr = dma_read32(DMA_CSR); if (csr & DMA_HNDL_ERROR) return 1; return 0; } static const struct esp_driver_ops sun3x_esp_ops = { .esp_write8 = sun3x_esp_write8, .esp_read8 = sun3x_esp_read8, .map_single = sun3x_esp_map_single, .map_sg = sun3x_esp_map_sg, .unmap_single = sun3x_esp_unmap_single, .unmap_sg = sun3x_esp_unmap_sg, .irq_pending = sun3x_esp_irq_pending, .reset_dma = sun3x_esp_reset_dma, .dma_drain = sun3x_esp_dma_drain, .dma_invalidate = sun3x_esp_dma_invalidate, .send_dma_cmd = sun3x_esp_send_dma_cmd, .dma_error = sun3x_esp_dma_error, }; static int __devinit esp_sun3x_probe(struct platform_device *dev) { struct scsi_host_template *tpnt = &scsi_esp_template; struct Scsi_Host *host; struct esp *esp; struct resource *res; int err = -ENOMEM; host = scsi_host_alloc(tpnt, sizeof(struct esp)); if (!host) goto fail; host->max_id = 8; esp = shost_priv(host); esp->host = host; esp->dev = dev; esp->ops = &sun3x_esp_ops; res = platform_get_resource(dev, IORESOURCE_MEM, 0); if (!res && !res->start) goto fail_unlink; esp->regs = ioremap_nocache(res->start, 0x20); if (!esp->regs) goto fail_unmap_regs; res = platform_get_resource(dev, IORESOURCE_MEM, 1); if (!res && !res->start) goto fail_unmap_regs; esp->dma_regs = ioremap_nocache(res->start, 0x10); esp->command_block = dma_alloc_coherent(esp->dev, 16, &esp->command_block_dma, GFP_KERNEL); if (!esp->command_block) goto fail_unmap_regs_dma; host->irq = platform_get_irq(dev, 0); err = request_irq(host->irq, scsi_esp_intr, IRQF_SHARED, "SUN3X ESP", esp); if (err < 0) goto fail_unmap_command_block; esp->scsi_id = 7; esp->host->this_id = esp->scsi_id; esp->scsi_id_mask = (1 << esp->scsi_id); esp->cfreq = 20000000; dev_set_drvdata(&dev->dev, esp); err = scsi_esp_register(esp, &dev->dev); if (err) goto fail_free_irq; return 0; fail_free_irq: free_irq(host->irq, esp); fail_unmap_command_block: dma_free_coherent(esp->dev, 16, esp->command_block, esp->command_block_dma); fail_unmap_regs_dma: iounmap(esp->dma_regs); fail_unmap_regs: iounmap(esp->regs); fail_unlink: scsi_host_put(host); fail: return err; } static int __devexit esp_sun3x_remove(struct platform_device *dev) { struct esp *esp = dev_get_drvdata(&dev->dev); unsigned int irq = esp->host->irq; u32 val; scsi_esp_unregister(esp); /* Disable interrupts. */ val = dma_read32(DMA_CSR); dma_write32(val & ~DMA_INT_ENAB, DMA_CSR); free_irq(irq, esp); dma_free_coherent(esp->dev, 16, esp->command_block, esp->command_block_dma); scsi_host_put(esp->host); return 0; } static struct platform_driver esp_sun3x_driver = { .probe = esp_sun3x_probe, .remove = __devexit_p(esp_sun3x_remove), .driver = { .name = "sun3x_esp", .owner = THIS_MODULE, }, }; static int __init sun3x_esp_init(void) { return platform_driver_register(&esp_sun3x_driver); } static void __exit sun3x_esp_exit(void) { platform_driver_unregister(&esp_sun3x_driver); } MODULE_DESCRIPTION("Sun3x ESP SCSI driver"); MODULE_AUTHOR("Thomas Bogendoerfer (tsbogend@alpha.franken.de)"); MODULE_LICENSE("GPL"); MODULE_VERSION(DRV_VERSION); module_init(sun3x_esp_init); module_exit(sun3x_esp_exit); MODULE_ALIAS("platform:sun3x_esp");