// 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, }, }; static int __init mac_esp_init(void) { return platform_driver_register(&esp_mac_driver); } static void __exit mac_esp_exit(void) { platform_driver_unregister(&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); module_init(mac_esp_init); module_exit(mac_esp_exit);