drivers/scsi/a3000.c - linux - Git at Google

 // 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 const 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 = &regs->SASR;
 	wdregs.SCMD = &regs->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 void __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));
 }

 /*
  * amiga_a3000_scsi_remove() lives in .exit.text. For drivers registered via
  * module_platform_driver_probe() this is ok because they cannot get unbound at
  * runtime. So mark the driver struct with __refdata to prevent modpost
  * triggering a section mismatch warning.
  */
 static struct platform_driver amiga_a3000_scsi_driver __refdata = {
 	.remove_new = __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");
	// 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 const 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 = &regs->SASR;
	wdregs.SCMD = &regs->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 void __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));
	}

	/*
	* amiga_a3000_scsi_remove() lives in .exit.text. For drivers registered via
	* module_platform_driver_probe() this is ok because they cannot get unbound at
	* runtime. So mark the driver struct with __refdata to prevent modpost
	* triggering a section mismatch warning.
	*/
	static struct platform_driver amiga_a3000_scsi_driver __refdata = {
	.remove_new = __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");