ide: move SFF DMA code to ide-dma-sff.c
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-dma-sff.c b/drivers/ide/ide-dma-sff.c
new file mode 100644
index 0000000..0903782
--- /dev/null
+++ b/drivers/ide/ide-dma-sff.c
@@ -0,0 +1,356 @@
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/ide.h>
+#include <linux/scatterlist.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+
+/**
+ * config_drive_for_dma - attempt to activate IDE DMA
+ * @drive: the drive to place in DMA mode
+ *
+ * If the drive supports at least mode 2 DMA or UDMA of any kind
+ * then attempt to place it into DMA mode. Drives that are known to
+ * support DMA but predate the DMA properties or that are known
+ * to have DMA handling bugs are also set up appropriately based
+ * on the good/bad drive lists.
+ */
+
+int config_drive_for_dma(ide_drive_t *drive)
+{
+ ide_hwif_t *hwif = drive->hwif;
+ u16 *id = drive->id;
+
+ if (drive->media != ide_disk) {
+ if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
+ return 0;
+ }
+
+ /*
+ * Enable DMA on any drive that has
+ * UltraDMA (mode 0/1/2/3/4/5/6) enabled
+ */
+ if ((id[ATA_ID_FIELD_VALID] & 4) &&
+ ((id[ATA_ID_UDMA_MODES] >> 8) & 0x7f))
+ return 1;
+
+ /*
+ * Enable DMA on any drive that has mode2 DMA
+ * (multi or single) enabled
+ */
+ if (id[ATA_ID_FIELD_VALID] & 2) /* regular DMA */
+ if ((id[ATA_ID_MWDMA_MODES] & 0x404) == 0x404 ||
+ (id[ATA_ID_SWDMA_MODES] & 0x404) == 0x404)
+ return 1;
+
+ /* Consult the list of known "good" drives */
+ if (ide_dma_good_drive(drive))
+ return 1;
+
+ return 0;
+}
+
+/**
+ * ide_dma_host_set - Enable/disable DMA on a host
+ * @drive: drive to control
+ *
+ * Enable/disable DMA on an IDE controller following generic
+ * bus-mastering IDE controller behaviour.
+ */
+
+void ide_dma_host_set(ide_drive_t *drive, int on)
+{
+ ide_hwif_t *hwif = drive->hwif;
+ u8 unit = drive->dn & 1;
+ u8 dma_stat = hwif->tp_ops->read_sff_dma_status(hwif);
+
+ if (on)
+ dma_stat |= (1 << (5 + unit));
+ else
+ dma_stat &= ~(1 << (5 + unit));
+
+ if (hwif->host_flags & IDE_HFLAG_MMIO)
+ writeb(dma_stat,
+ (void __iomem *)(hwif->dma_base + ATA_DMA_STATUS));
+ else
+ outb(dma_stat, hwif->dma_base + ATA_DMA_STATUS);
+}
+EXPORT_SYMBOL_GPL(ide_dma_host_set);
+
+/**
+ * ide_build_dmatable - build IDE DMA table
+ *
+ * ide_build_dmatable() prepares a dma request. We map the command
+ * to get the pci bus addresses of the buffers and then build up
+ * the PRD table that the IDE layer wants to be fed.
+ *
+ * Most chipsets correctly interpret a length of 0x0000 as 64KB,
+ * but at least one (e.g. CS5530) misinterprets it as zero (!).
+ * So we break the 64KB entry into two 32KB entries instead.
+ *
+ * Returns the number of built PRD entries if all went okay,
+ * returns 0 otherwise.
+ *
+ * May also be invoked from trm290.c
+ */
+
+int ide_build_dmatable(ide_drive_t *drive, struct request *rq)
+{
+ ide_hwif_t *hwif = drive->hwif;
+ __le32 *table = (__le32 *)hwif->dmatable_cpu;
+ unsigned int is_trm290 = (hwif->chipset == ide_trm290) ? 1 : 0;
+ unsigned int count = 0;
+ int i;
+ struct scatterlist *sg;
+
+ hwif->sg_nents = ide_build_sglist(drive, rq);
+ if (hwif->sg_nents == 0)
+ return 0;
+
+ for_each_sg(hwif->sg_table, sg, hwif->sg_nents, i) {
+ u32 cur_addr, cur_len, xcount, bcount;
+
+ cur_addr = sg_dma_address(sg);
+ cur_len = sg_dma_len(sg);
+
+ /*
+ * Fill in the dma table, without crossing any 64kB boundaries.
+ * Most hardware requires 16-bit alignment of all blocks,
+ * but the trm290 requires 32-bit alignment.
+ */
+
+ while (cur_len) {
+ if (count++ >= PRD_ENTRIES)
+ goto use_pio_instead;
+
+ bcount = 0x10000 - (cur_addr & 0xffff);
+ if (bcount > cur_len)
+ bcount = cur_len;
+ *table++ = cpu_to_le32(cur_addr);
+ xcount = bcount & 0xffff;
+ if (is_trm290)
+ xcount = ((xcount >> 2) - 1) << 16;
+ if (xcount == 0x0000) {
+ if (count++ >= PRD_ENTRIES)
+ goto use_pio_instead;
+ *table++ = cpu_to_le32(0x8000);
+ *table++ = cpu_to_le32(cur_addr + 0x8000);
+ xcount = 0x8000;
+ }
+ *table++ = cpu_to_le32(xcount);
+ cur_addr += bcount;
+ cur_len -= bcount;
+ }
+ }
+
+ if (count) {
+ if (!is_trm290)
+ *--table |= cpu_to_le32(0x80000000);
+ return count;
+ }
+
+use_pio_instead:
+ printk(KERN_ERR "%s: %s\n", drive->name,
+ count ? "DMA table too small" : "empty DMA table?");
+
+ ide_destroy_dmatable(drive);
+
+ return 0; /* revert to PIO for this request */
+}
+EXPORT_SYMBOL_GPL(ide_build_dmatable);
+
+/**
+ * ide_dma_setup - begin a DMA phase
+ * @drive: target device
+ *
+ * Build an IDE DMA PRD (IDE speak for scatter gather table)
+ * and then set up the DMA transfer registers for a device
+ * that follows generic IDE PCI DMA behaviour. Controllers can
+ * override this function if they need to
+ *
+ * Returns 0 on success. If a PIO fallback is required then 1
+ * is returned.
+ */
+
+int ide_dma_setup(ide_drive_t *drive)
+{
+ ide_hwif_t *hwif = drive->hwif;
+ struct request *rq = hwif->hwgroup->rq;
+ unsigned int reading;
+ u8 mmio = (hwif->host_flags & IDE_HFLAG_MMIO) ? 1 : 0;
+ u8 dma_stat;
+
+ if (rq_data_dir(rq))
+ reading = 0;
+ else
+ reading = 1 << 3;
+
+ /* fall back to pio! */
+ if (!ide_build_dmatable(drive, rq)) {
+ ide_map_sg(drive, rq);
+ return 1;
+ }
+
+ /* PRD table */
+ if (hwif->host_flags & IDE_HFLAG_MMIO)
+ writel(hwif->dmatable_dma,
+ (void __iomem *)(hwif->dma_base + ATA_DMA_TABLE_OFS));
+ else
+ outl(hwif->dmatable_dma, hwif->dma_base + ATA_DMA_TABLE_OFS);
+
+ /* specify r/w */
+ if (mmio)
+ writeb(reading, (void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
+ else
+ outb(reading, hwif->dma_base + ATA_DMA_CMD);
+
+ /* read DMA status for INTR & ERROR flags */
+ dma_stat = hwif->tp_ops->read_sff_dma_status(hwif);
+
+ /* clear INTR & ERROR flags */
+ if (mmio)
+ writeb(dma_stat | 6,
+ (void __iomem *)(hwif->dma_base + ATA_DMA_STATUS));
+ else
+ outb(dma_stat | 6, hwif->dma_base + ATA_DMA_STATUS);
+
+ drive->waiting_for_dma = 1;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ide_dma_setup);
+
+/**
+ * dma_timer_expiry - handle a DMA timeout
+ * @drive: Drive that timed out
+ *
+ * An IDE DMA transfer timed out. In the event of an error we ask
+ * the driver to resolve the problem, if a DMA transfer is still
+ * in progress we continue to wait (arguably we need to add a
+ * secondary 'I don't care what the drive thinks' timeout here)
+ * Finally if we have an interrupt we let it complete the I/O.
+ * But only one time - we clear expiry and if it's still not
+ * completed after WAIT_CMD, we error and retry in PIO.
+ * This can occur if an interrupt is lost or due to hang or bugs.
+ */
+
+static int dma_timer_expiry(ide_drive_t *drive)
+{
+ ide_hwif_t *hwif = drive->hwif;
+ u8 dma_stat = hwif->tp_ops->read_sff_dma_status(hwif);
+
+ printk(KERN_WARNING "%s: %s: DMA status (0x%02x)\n",
+ drive->name, __func__, dma_stat);
+
+ if ((dma_stat & 0x18) == 0x18) /* BUSY Stupid Early Timer !! */
+ return WAIT_CMD;
+
+ hwif->hwgroup->expiry = NULL; /* one free ride for now */
+
+ /* 1 dmaing, 2 error, 4 intr */
+ if (dma_stat & 2) /* ERROR */
+ return -1;
+
+ if (dma_stat & 1) /* DMAing */
+ return WAIT_CMD;
+
+ if (dma_stat & 4) /* Got an Interrupt */
+ return WAIT_CMD;
+
+ return 0; /* Status is unknown -- reset the bus */
+}
+
+void ide_dma_exec_cmd(ide_drive_t *drive, u8 command)
+{
+ /* issue cmd to drive */
+ ide_execute_command(drive, command, &ide_dma_intr, 2 * WAIT_CMD,
+ dma_timer_expiry);
+}
+EXPORT_SYMBOL_GPL(ide_dma_exec_cmd);
+
+void ide_dma_start(ide_drive_t *drive)
+{
+ ide_hwif_t *hwif = drive->hwif;
+ u8 dma_cmd;
+
+ /* Note that this is done *after* the cmd has
+ * been issued to the drive, as per the BM-IDE spec.
+ * The Promise Ultra33 doesn't work correctly when
+ * we do this part before issuing the drive cmd.
+ */
+ if (hwif->host_flags & IDE_HFLAG_MMIO) {
+ dma_cmd = readb((void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
+ /* start DMA */
+ writeb(dma_cmd | 1,
+ (void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
+ } else {
+ dma_cmd = inb(hwif->dma_base + ATA_DMA_CMD);
+ outb(dma_cmd | 1, hwif->dma_base + ATA_DMA_CMD);
+ }
+
+ wmb();
+}
+EXPORT_SYMBOL_GPL(ide_dma_start);
+
+/* returns 1 on error, 0 otherwise */
+int ide_dma_end(ide_drive_t *drive)
+{
+ ide_hwif_t *hwif = drive->hwif;
+ u8 mmio = (hwif->host_flags & IDE_HFLAG_MMIO) ? 1 : 0;
+ u8 dma_stat = 0, dma_cmd = 0;
+
+ drive->waiting_for_dma = 0;
+
+ if (mmio) {
+ /* get DMA command mode */
+ dma_cmd = readb((void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
+ /* stop DMA */
+ writeb(dma_cmd & ~1,
+ (void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
+ } else {
+ dma_cmd = inb(hwif->dma_base + ATA_DMA_CMD);
+ outb(dma_cmd & ~1, hwif->dma_base + ATA_DMA_CMD);
+ }
+
+ /* get DMA status */
+ dma_stat = hwif->tp_ops->read_sff_dma_status(hwif);
+
+ if (mmio)
+ /* clear the INTR & ERROR bits */
+ writeb(dma_stat | 6,
+ (void __iomem *)(hwif->dma_base + ATA_DMA_STATUS));
+ else
+ outb(dma_stat | 6, hwif->dma_base + ATA_DMA_STATUS);
+
+ /* purge DMA mappings */
+ ide_destroy_dmatable(drive);
+ /* verify good DMA status */
+ wmb();
+ return (dma_stat & 7) != 4 ? (0x10 | dma_stat) : 0;
+}
+EXPORT_SYMBOL_GPL(ide_dma_end);
+
+/* returns 1 if dma irq issued, 0 otherwise */
+int ide_dma_test_irq(ide_drive_t *drive)
+{
+ ide_hwif_t *hwif = drive->hwif;
+ u8 dma_stat = hwif->tp_ops->read_sff_dma_status(hwif);
+
+ /* return 1 if INTR asserted */
+ if ((dma_stat & 4) == 4)
+ return 1;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ide_dma_test_irq);
+
+const struct ide_dma_ops sff_dma_ops = {
+ .dma_host_set = ide_dma_host_set,
+ .dma_setup = ide_dma_setup,
+ .dma_exec_cmd = ide_dma_exec_cmd,
+ .dma_start = ide_dma_start,
+ .dma_end = ide_dma_end,
+ .dma_test_irq = ide_dma_test_irq,
+ .dma_timeout = ide_dma_timeout,
+ .dma_lost_irq = ide_dma_lost_irq,
+};
+EXPORT_SYMBOL_GPL(sff_dma_ops);