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Diffstat (limited to '')
| -rw-r--r-- | drivers/scsi/a3000.c | 310 |
1 files changed, 310 insertions, 0 deletions
diff --git a/drivers/scsi/a3000.c b/drivers/scsi/a3000.c new file mode 100644 index 000000000..2c5cb1a02 --- /dev/null +++ b/drivers/scsi/a3000.c @@ -0,0 +1,310 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <linux/types.h> +#include <linux/mm.h> +#include <linux/ioport.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/dma-mapping.h> +#include <linux/module.h> + +#include <asm/page.h> +#include <asm/amigaints.h> +#include <asm/amigahw.h> + +#include <scsi/scsi.h> +#include <scsi/scsi_cmnd.h> +#include <scsi/scsi_device.h> +#include <scsi/scsi_eh.h> +#include <scsi/scsi_tcq.h> +#include "wd33c93.h" +#include "a3000.h" + + +struct a3000_hostdata { + struct WD33C93_hostdata wh; + struct a3000_scsiregs *regs; + struct device *dev; +}; + +#define DMA_DIR(d) ((d == DATA_OUT_DIR) ? DMA_TO_DEVICE : DMA_FROM_DEVICE) + +static irqreturn_t a3000_intr(int irq, void *data) +{ + struct Scsi_Host *instance = data; + struct a3000_hostdata *hdata = shost_priv(instance); + unsigned int status = hdata->regs->ISTR; + unsigned long flags; + + if (!(status & ISTR_INT_P)) + return IRQ_NONE; + if (status & ISTR_INTS) { + spin_lock_irqsave(instance->host_lock, flags); + wd33c93_intr(instance); + spin_unlock_irqrestore(instance->host_lock, flags); + return IRQ_HANDLED; + } + pr_warn("Non-serviced A3000 SCSI-interrupt? ISTR = %02x\n", status); + return IRQ_NONE; +} + +static int dma_setup(struct scsi_cmnd *cmd, int dir_in) +{ + struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd); + unsigned long len = scsi_pointer->this_residual; + struct Scsi_Host *instance = cmd->device->host; + struct a3000_hostdata *hdata = shost_priv(instance); + struct WD33C93_hostdata *wh = &hdata->wh; + struct a3000_scsiregs *regs = hdata->regs; + unsigned short cntr = CNTR_PDMD | CNTR_INTEN; + dma_addr_t addr; + + addr = dma_map_single(hdata->dev, scsi_pointer->ptr, + len, DMA_DIR(dir_in)); + if (dma_mapping_error(hdata->dev, addr)) { + dev_warn(hdata->dev, "cannot map SCSI data block %p\n", + scsi_pointer->ptr); + return 1; + } + scsi_pointer->dma_handle = addr; + + /* + * if the physical address has the wrong alignment, or if + * physical address is bad, or if it is a write and at the + * end of a physical memory chunk, then allocate a bounce + * buffer + * MSch 20220629 - only wrong alignment tested - bounce + * buffer returned by kmalloc is guaranteed to be aligned + */ + if (addr & A3000_XFER_MASK) { + WARN_ONCE(1, "Invalid alignment for DMA!"); + /* drop useless mapping */ + dma_unmap_single(hdata->dev, scsi_pointer->dma_handle, + scsi_pointer->this_residual, + DMA_DIR(dir_in)); + + wh->dma_bounce_len = (scsi_pointer->this_residual + 511) & ~0x1ff; + wh->dma_bounce_buffer = kmalloc(wh->dma_bounce_len, + GFP_KERNEL); + + /* can't allocate memory; use PIO */ + if (!wh->dma_bounce_buffer) { + wh->dma_bounce_len = 0; + scsi_pointer->dma_handle = (dma_addr_t) NULL; + return 1; + } + + if (!dir_in) { + /* copy to bounce buffer for a write */ + memcpy(wh->dma_bounce_buffer, scsi_pointer->ptr, + scsi_pointer->this_residual); + } + + addr = dma_map_single(hdata->dev, scsi_pointer->ptr, + len, DMA_DIR(dir_in)); + if (dma_mapping_error(hdata->dev, addr)) { + dev_warn(hdata->dev, + "cannot map SCSI data block %p\n", + scsi_pointer->ptr); + return 1; + } + scsi_pointer->dma_handle = addr; + } + + /* setup dma direction */ + if (!dir_in) + cntr |= CNTR_DDIR; + + /* remember direction */ + wh->dma_dir = dir_in; + + regs->CNTR = cntr; + + /* setup DMA *physical* address */ + regs->ACR = addr; + + /* no more cache flush here - dma_map_single() takes care */ + + /* start DMA */ + mb(); /* make sure setup is completed */ + regs->ST_DMA = 1; + mb(); /* make sure DMA has started before next IO */ + + /* return success */ + return 0; +} + +static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt, + int status) +{ + struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(SCpnt); + struct a3000_hostdata *hdata = shost_priv(instance); + struct WD33C93_hostdata *wh = &hdata->wh; + struct a3000_scsiregs *regs = hdata->regs; + + /* disable SCSI interrupts */ + unsigned short cntr = CNTR_PDMD; + + if (!wh->dma_dir) + cntr |= CNTR_DDIR; + + regs->CNTR = cntr; + mb(); /* make sure CNTR is updated before next IO */ + + /* flush if we were reading */ + if (wh->dma_dir) { + regs->FLUSH = 1; + mb(); /* don't allow prefetch */ + while (!(regs->ISTR & ISTR_FE_FLG)) + barrier(); + mb(); /* no IO until FLUSH is done */ + } + + /* clear a possible interrupt */ + /* I think that this CINT is only necessary if you are + * using the terminal count features. HM 7 Mar 1994 + */ + regs->CINT = 1; + + /* stop DMA */ + regs->SP_DMA = 1; + mb(); /* make sure DMA is stopped before next IO */ + + /* restore the CONTROL bits (minus the direction flag) */ + regs->CNTR = CNTR_PDMD | CNTR_INTEN; + mb(); /* make sure CNTR is updated before next IO */ + + dma_unmap_single(hdata->dev, scsi_pointer->dma_handle, + scsi_pointer->this_residual, + DMA_DIR(wh->dma_dir)); + + /* copy from a bounce buffer, if necessary */ + if (status && wh->dma_bounce_buffer) { + if (SCpnt) { + if (wh->dma_dir && SCpnt) + memcpy(scsi_pointer->ptr, wh->dma_bounce_buffer, + scsi_pointer->this_residual); + kfree(wh->dma_bounce_buffer); + wh->dma_bounce_buffer = NULL; + wh->dma_bounce_len = 0; + } else { + kfree(wh->dma_bounce_buffer); + wh->dma_bounce_buffer = NULL; + wh->dma_bounce_len = 0; + } + } +} + +static struct scsi_host_template amiga_a3000_scsi_template = { + .module = THIS_MODULE, + .name = "Amiga 3000 built-in SCSI", + .show_info = wd33c93_show_info, + .write_info = wd33c93_write_info, + .proc_name = "A3000", + .queuecommand = wd33c93_queuecommand, + .eh_abort_handler = wd33c93_abort, + .eh_host_reset_handler = wd33c93_host_reset, + .can_queue = CAN_QUEUE, + .this_id = 7, + .sg_tablesize = SG_ALL, + .cmd_per_lun = CMD_PER_LUN, + .cmd_size = sizeof(struct scsi_pointer), +}; + +static int __init amiga_a3000_scsi_probe(struct platform_device *pdev) +{ + struct resource *res; + struct Scsi_Host *instance; + int error; + struct a3000_scsiregs *regs; + wd33c93_regs wdregs; + struct a3000_hostdata *hdata; + + if (dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32))) { + dev_warn(&pdev->dev, "cannot use 32 bit DMA\n"); + return -ENODEV; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + + if (!request_mem_region(res->start, resource_size(res), "wd33c93")) + return -EBUSY; + + instance = scsi_host_alloc(&amiga_a3000_scsi_template, + sizeof(struct a3000_hostdata)); + if (!instance) { + error = -ENOMEM; + goto fail_alloc; + } + + instance->irq = IRQ_AMIGA_PORTS; + + regs = ZTWO_VADDR(res->start); + regs->DAWR = DAWR_A3000; + + wdregs.SASR = ®s->SASR; + wdregs.SCMD = ®s->SCMD; + + hdata = shost_priv(instance); + hdata->dev = &pdev->dev; + hdata->wh.no_sync = 0xff; + hdata->wh.fast = 0; + hdata->wh.dma_mode = CTRL_DMA; + hdata->regs = regs; + + wd33c93_init(instance, wdregs, dma_setup, dma_stop, WD33C93_FS_12_15); + error = request_irq(IRQ_AMIGA_PORTS, a3000_intr, IRQF_SHARED, + "A3000 SCSI", instance); + if (error) + goto fail_irq; + + regs->CNTR = CNTR_PDMD | CNTR_INTEN; + + error = scsi_add_host(instance, NULL); + if (error) + goto fail_host; + + platform_set_drvdata(pdev, instance); + + scsi_scan_host(instance); + return 0; + +fail_host: + free_irq(IRQ_AMIGA_PORTS, instance); +fail_irq: + scsi_host_put(instance); +fail_alloc: + release_mem_region(res->start, resource_size(res)); + return error; +} + +static int __exit amiga_a3000_scsi_remove(struct platform_device *pdev) +{ + struct Scsi_Host *instance = platform_get_drvdata(pdev); + struct a3000_hostdata *hdata = shost_priv(instance); + struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + + hdata->regs->CNTR = 0; + scsi_remove_host(instance); + free_irq(IRQ_AMIGA_PORTS, instance); + scsi_host_put(instance); + release_mem_region(res->start, resource_size(res)); + return 0; +} + +static struct platform_driver amiga_a3000_scsi_driver = { + .remove = __exit_p(amiga_a3000_scsi_remove), + .driver = { + .name = "amiga-a3000-scsi", + }, +}; + +module_platform_driver_probe(amiga_a3000_scsi_driver, amiga_a3000_scsi_probe); + +MODULE_DESCRIPTION("Amiga 3000 built-in SCSI"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:amiga-a3000-scsi"); |