diff options
Diffstat (limited to 'drivers/scsi/mac_esp.c')
-rw-r--r-- | drivers/scsi/mac_esp.c | 448 |
1 files changed, 448 insertions, 0 deletions
diff --git a/drivers/scsi/mac_esp.c b/drivers/scsi/mac_esp.c new file mode 100644 index 000000000..6d23ab5ae --- /dev/null +++ b/drivers/scsi/mac_esp.c @@ -0,0 +1,448 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* mac_esp.c: ESP front-end for Macintosh Quadra systems. + * + * Adapted from jazz_esp.c and the old mac_esp.c. + * + * The pseudo DMA algorithm is based on the one used in NetBSD. + * See sys/arch/mac68k/obio/esp.c for some background information. + * + * Copyright (C) 2007-2008 Finn Thain + */ + +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/dma-mapping.h> +#include <linux/scatterlist.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/nubus.h> +#include <linux/slab.h> + +#include <asm/irq.h> +#include <asm/dma.h> +#include <asm/macints.h> +#include <asm/macintosh.h> +#include <asm/mac_via.h> + +#include <scsi/scsi_host.h> + +#include "esp_scsi.h" + +#define DRV_MODULE_NAME "mac_esp" +#define PFX DRV_MODULE_NAME ": " +#define DRV_VERSION "1.000" +#define DRV_MODULE_RELDATE "Sept 15, 2007" + +#define MAC_ESP_IO_BASE 0x50F00000 +#define MAC_ESP_REGS_QUADRA (MAC_ESP_IO_BASE + 0x10000) +#define MAC_ESP_REGS_QUADRA2 (MAC_ESP_IO_BASE + 0xF000) +#define MAC_ESP_REGS_QUADRA3 (MAC_ESP_IO_BASE + 0x18000) +#define MAC_ESP_REGS_SPACING 0x402 +#define MAC_ESP_PDMA_REG 0xF9800024 +#define MAC_ESP_PDMA_REG_SPACING 0x4 +#define MAC_ESP_PDMA_IO_OFFSET 0x100 + +#define esp_read8(REG) mac_esp_read8(esp, REG) +#define esp_write8(VAL, REG) mac_esp_write8(esp, VAL, REG) + +struct mac_esp_priv { + struct esp *esp; + void __iomem *pdma_regs; + void __iomem *pdma_io; +}; +static struct esp *esp_chips[2]; +static DEFINE_SPINLOCK(esp_chips_lock); + +#define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \ + dev_get_drvdata((esp)->dev)) + +static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg) +{ + nubus_writeb(val, esp->regs + reg * 16); +} + +static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg) +{ + return nubus_readb(esp->regs + reg * 16); +} + +static void mac_esp_reset_dma(struct esp *esp) +{ + /* Nothing to do. */ +} + +static void mac_esp_dma_drain(struct esp *esp) +{ + /* Nothing to do. */ +} + +static void mac_esp_dma_invalidate(struct esp *esp) +{ + /* Nothing to do. */ +} + +static int mac_esp_dma_error(struct esp *esp) +{ + return esp->send_cmd_error; +} + +static inline int mac_esp_wait_for_empty_fifo(struct esp *esp) +{ + int i = 500000; + + do { + if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES)) + return 0; + + if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) + return 1; + + udelay(2); + } while (--i); + + printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n", + esp_read8(ESP_STATUS)); + esp->send_cmd_error = 1; + return 1; +} + +static inline int mac_esp_wait_for_dreq(struct esp *esp) +{ + struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); + int i = 500000; + + do { + if (mep->pdma_regs == NULL) { + if (via2_scsi_drq_pending()) + return 0; + } else { + if (nubus_readl(mep->pdma_regs) & 0x200) + return 0; + } + + if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) + return 1; + + udelay(2); + } while (--i); + + printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n", + esp_read8(ESP_STATUS)); + esp->send_cmd_error = 1; + return 1; +} + +#define MAC_ESP_PDMA_LOOP(operands) \ + asm volatile ( \ + " tstw %1 \n" \ + " jbeq 20f \n" \ + "1: movew " operands " \n" \ + "2: movew " operands " \n" \ + "3: movew " operands " \n" \ + "4: movew " operands " \n" \ + "5: movew " operands " \n" \ + "6: movew " operands " \n" \ + "7: movew " operands " \n" \ + "8: movew " operands " \n" \ + "9: movew " operands " \n" \ + "10: movew " operands " \n" \ + "11: movew " operands " \n" \ + "12: movew " operands " \n" \ + "13: movew " operands " \n" \ + "14: movew " operands " \n" \ + "15: movew " operands " \n" \ + "16: movew " operands " \n" \ + " subqw #1,%1 \n" \ + " jbne 1b \n" \ + "20: tstw %2 \n" \ + " jbeq 30f \n" \ + "21: movew " operands " \n" \ + " subqw #1,%2 \n" \ + " jbne 21b \n" \ + "30: tstw %3 \n" \ + " jbeq 40f \n" \ + "31: moveb " operands " \n" \ + "32: nop \n" \ + "40: \n" \ + " \n" \ + " .section __ex_table,\"a\" \n" \ + " .align 4 \n" \ + " .long 1b,40b \n" \ + " .long 2b,40b \n" \ + " .long 3b,40b \n" \ + " .long 4b,40b \n" \ + " .long 5b,40b \n" \ + " .long 6b,40b \n" \ + " .long 7b,40b \n" \ + " .long 8b,40b \n" \ + " .long 9b,40b \n" \ + " .long 10b,40b \n" \ + " .long 11b,40b \n" \ + " .long 12b,40b \n" \ + " .long 13b,40b \n" \ + " .long 14b,40b \n" \ + " .long 15b,40b \n" \ + " .long 16b,40b \n" \ + " .long 21b,40b \n" \ + " .long 31b,40b \n" \ + " .long 32b,40b \n" \ + " .previous \n" \ + : "+a" (addr), "+r" (count32), "+r" (count2) \ + : "g" (count1), "a" (mep->pdma_io)) + +static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count, + u32 dma_count, int write, u8 cmd) +{ + struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); + + esp->send_cmd_error = 0; + + if (!write) + scsi_esp_cmd(esp, ESP_CMD_FLUSH); + + esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW); + esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED); + + scsi_esp_cmd(esp, cmd); + + do { + unsigned int count32 = esp_count >> 5; + unsigned int count2 = (esp_count & 0x1F) >> 1; + unsigned int count1 = esp_count & 1; + unsigned int start_addr = addr; + + if (mac_esp_wait_for_dreq(esp)) + break; + + if (write) { + MAC_ESP_PDMA_LOOP("%4@,%0@+"); + + esp_count -= addr - start_addr; + } else { + unsigned int n; + + MAC_ESP_PDMA_LOOP("%0@+,%4@"); + + if (mac_esp_wait_for_empty_fifo(esp)) + break; + + n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW); + addr = start_addr + esp_count - n; + esp_count = n; + } + } while (esp_count); +} + +static int mac_esp_irq_pending(struct esp *esp) +{ + if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) + return 1; + return 0; +} + +static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len) +{ + return dma_len > 0xFFFF ? 0xFFFF : dma_len; +} + +static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id) +{ + int got_intr; + + /* + * This is an edge triggered IRQ, so we have to be careful to + * avoid missing a transition when it is shared by two ESP devices. + */ + + do { + got_intr = 0; + if (esp_chips[0] && + (mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) { + (void)scsi_esp_intr(irq, esp_chips[0]); + got_intr = 1; + } + if (esp_chips[1] && + (mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) { + (void)scsi_esp_intr(irq, esp_chips[1]); + got_intr = 1; + } + } while (got_intr); + + return IRQ_HANDLED; +} + +static struct esp_driver_ops mac_esp_ops = { + .esp_write8 = mac_esp_write8, + .esp_read8 = mac_esp_read8, + .irq_pending = mac_esp_irq_pending, + .dma_length_limit = mac_esp_dma_length_limit, + .reset_dma = mac_esp_reset_dma, + .dma_drain = mac_esp_dma_drain, + .dma_invalidate = mac_esp_dma_invalidate, + .send_dma_cmd = mac_esp_send_pdma_cmd, + .dma_error = mac_esp_dma_error, +}; + +static int esp_mac_probe(struct platform_device *dev) +{ + struct scsi_host_template *tpnt = &scsi_esp_template; + struct Scsi_Host *host; + struct esp *esp; + int err; + struct mac_esp_priv *mep; + + if (!MACH_IS_MAC) + return -ENODEV; + + if (dev->id > 1) + return -ENODEV; + + host = scsi_host_alloc(tpnt, sizeof(struct esp)); + + err = -ENOMEM; + if (!host) + goto fail; + + host->max_id = 8; + host->dma_boundary = PAGE_SIZE - 1; + esp = shost_priv(host); + + esp->host = host; + esp->dev = &dev->dev; + + esp->command_block = kzalloc(16, GFP_KERNEL); + if (!esp->command_block) + goto fail_unlink; + esp->command_block_dma = (dma_addr_t)esp->command_block; + + esp->scsi_id = 7; + host->this_id = esp->scsi_id; + esp->scsi_id_mask = 1 << esp->scsi_id; + + mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL); + if (!mep) + goto fail_free_command_block; + mep->esp = esp; + platform_set_drvdata(dev, mep); + + switch (macintosh_config->scsi_type) { + case MAC_SCSI_QUADRA: + esp->cfreq = 16500000; + esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA; + mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET; + mep->pdma_regs = NULL; + break; + case MAC_SCSI_QUADRA2: + esp->cfreq = 25000000; + esp->regs = (void __iomem *)(MAC_ESP_REGS_QUADRA2 + + dev->id * MAC_ESP_REGS_SPACING); + mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET; + mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG + + dev->id * MAC_ESP_PDMA_REG_SPACING); + nubus_writel(0x1d1, mep->pdma_regs); + break; + case MAC_SCSI_QUADRA3: + /* These quadras have a real DMA controller (the PSC) but we + * don't know how to drive it so we must use PIO instead. + */ + esp->cfreq = 25000000; + esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA3; + mep->pdma_io = NULL; + mep->pdma_regs = NULL; + break; + } + esp->fifo_reg = esp->regs + ESP_FDATA * 16; + + esp->ops = &mac_esp_ops; + esp->flags = ESP_FLAG_NO_DMA_MAP; + if (mep->pdma_io == NULL) { + printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id); + esp_write8(0, ESP_TCLOW); + esp_write8(0, ESP_TCMED); + esp->flags |= ESP_FLAG_DISABLE_SYNC; + mac_esp_ops.send_dma_cmd = esp_send_pio_cmd; + } else { + printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id); + } + + host->irq = IRQ_MAC_SCSI; + + /* The request_irq() call is intended to succeed for the first device + * and fail for the second device. + */ + err = request_irq(host->irq, mac_scsi_esp_intr, 0, "ESP", NULL); + spin_lock(&esp_chips_lock); + if (err < 0 && esp_chips[!dev->id] == NULL) { + spin_unlock(&esp_chips_lock); + goto fail_free_priv; + } + esp_chips[dev->id] = esp; + spin_unlock(&esp_chips_lock); + + err = scsi_esp_register(esp); + if (err) + goto fail_free_irq; + + return 0; + +fail_free_irq: + spin_lock(&esp_chips_lock); + esp_chips[dev->id] = NULL; + if (esp_chips[!dev->id] == NULL) { + spin_unlock(&esp_chips_lock); + free_irq(host->irq, NULL); + } else + spin_unlock(&esp_chips_lock); +fail_free_priv: + kfree(mep); +fail_free_command_block: + kfree(esp->command_block); +fail_unlink: + scsi_host_put(host); +fail: + return err; +} + +static int esp_mac_remove(struct platform_device *dev) +{ + struct mac_esp_priv *mep = platform_get_drvdata(dev); + struct esp *esp = mep->esp; + unsigned int irq = esp->host->irq; + + scsi_esp_unregister(esp); + + spin_lock(&esp_chips_lock); + esp_chips[dev->id] = NULL; + if (esp_chips[!dev->id] == NULL) { + spin_unlock(&esp_chips_lock); + free_irq(irq, NULL); + } else + spin_unlock(&esp_chips_lock); + + kfree(mep); + + kfree(esp->command_block); + + scsi_host_put(esp->host); + + return 0; +} + +static struct platform_driver esp_mac_driver = { + .probe = esp_mac_probe, + .remove = esp_mac_remove, + .driver = { + .name = DRV_MODULE_NAME, + }, +}; +module_platform_driver(esp_mac_driver); + +MODULE_DESCRIPTION("Mac ESP SCSI driver"); +MODULE_AUTHOR("Finn Thain"); +MODULE_LICENSE("GPL v2"); +MODULE_VERSION(DRV_VERSION); +MODULE_ALIAS("platform:" DRV_MODULE_NAME); |