summaryrefslogtreecommitdiffstats
path: root/drivers/scsi/sun3x_esp.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--drivers/scsi/sun3x_esp.c281
1 files changed, 281 insertions, 0 deletions
diff --git a/drivers/scsi/sun3x_esp.c b/drivers/scsi/sun3x_esp.c
new file mode 100644
index 000000000..d3489ac7a
--- /dev/null
+++ b/drivers/scsi/sun3x_esp.c
@@ -0,0 +1,281 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* 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/gfp.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 <linux/io.h>
+
+#include <asm/sun3x.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 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,
+ .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 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->dev;
+ esp->ops = &sun3x_esp_ops;
+
+ res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+ if (!res || !res->start)
+ goto fail_unlink;
+
+ esp->regs = ioremap(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(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 = err = platform_get_irq(dev, 0);
+ if (err < 0)
+ goto fail_unmap_command_block;
+ 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);
+ 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 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 = esp_sun3x_remove,
+ .driver = {
+ .name = "sun3x_esp",
+ },
+};
+module_platform_driver(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_ALIAS("platform:sun3x_esp");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 04:33:31 +0000