[PATCH 41/86] pata_efar: unify code for programming PIO and MWDMA timings

Bartlomiej Zolnierkiewicz
2009-11-25T17:07:58Z

From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Subject: [PATCH] pata_it8213: unify code for programming PIO and MWDMA timings

It results in ~9% decrease in the driver LOC count and also ~6%
decrease in the driver binary size (as measured on x86-32).

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
---
drivers/ata/pata_it8213.c | 87 +++++++++++++++-------------------------------
1 file changed, 29 insertions(+), 58 deletions(-)

Index: b/drivers/ata/pata_it8213.c
===================================================================
--- a/drivers/ata/pata_it8213.c
+++ b/drivers/ata/pata_it8213.c
@@ -61,20 +61,9 @@ static int it8213_cable_detect(struct at
return ATA_CBL_PATA80;
}

-/**
- * it8213_set_piomode - Initialize host controller PATA PIO timings
- * @ap: Port whose timings we are configuring
- * @adev: Device whose timings we are configuring
- *
- * Set PIO mode for device, in host controller PCI config space.
- *
- * LOCKING:
- * None (inherited from caller).
- */
-
-static void it8213_set_piomode (struct ata_port *ap, struct ata_device *adev)
+static void it8213_set_timings(struct ata_port *ap, struct ata_device *adev,
+ u8 pio, bool use_mwdma)
{
- unsigned int pio = adev->pio_mode - XFER_PIO_0;
struct pci_dev *dev = to_pci_dev(ap->host->dev);
u8 master_port = ap->port_no ? 0x42 : 0x40;
u16 master_data;
@@ -92,13 +81,18 @@ static void it8213_set_piomode (struct a
{ 2, 1 },
{ 2, 3 }, };

- if (pio > 1)
+ if (pio > 1 || use_mwdma)
control |= 1; /* TIME */
- if (ata_pio_need_iordy(adev)) /* PIO 3/4 require IORDY */
+ if (ata_pio_need_iordy(adev) || use_mwdma)
control |= 2; /* IE */
/* Bit 2 is set for ATAPI on the IT8213 - reverse of ICH/PIIX */
if (adev->class != ATA_DEV_ATA)
control |= 4; /* PPE */
+ /* If the drive MWDMA is faster than it can do PIO then
+ we must force PIO into PIO0 */
+ if (use_mwdma && adev->pio_mode < (XFER_PIO_0 + pio))
+ /* Enable DMA timing only */
+ control |= 8; /* PIO cycles in PIO0 */

pci_read_config_word(dev, master_port, &master_data);

@@ -127,6 +121,22 @@ static void it8213_set_piomode (struct a
}

/**
+ * it8213_set_piomode - Initialize host controller PATA PIO timings
+ * @ap: Port whose timings we are configuring
+ * @adev: Device whose timings we are configuring
+ *
+ * Set PIO mode for device, in host controller PCI config space.
+ *
+ * LOCKING:
+ * None (inherited from caller).
+ */
+
+static void it8213_set_piomode(struct ata_port *ap, struct ata_device *adev)
+{
+ it8213_set_timings(ap, adev, adev->pio_mode - XFER_PIO_0, 0);
+}
+
+/**
* it8213_set_dmamode - Initialize host controller PATA DMA timings
* @ap: Port whose timings we are configuring
* @adev: Device to program
@@ -141,23 +151,14 @@ static void it8213_set_piomode (struct a
static void it8213_set_dmamode (struct ata_port *ap, struct ata_device *adev)
{
struct pci_dev *dev = to_pci_dev(ap->host->dev);
- u16 master_data;
u8 speed = adev->dma_mode;
int devid = adev->devno;
u8 udma_enable;

- static const /* ISP RTC */
- u8 timings[][2] = { { 0, 0 },
- { 0, 0 },
- { 1, 0 },
- { 2, 1 },
- { 2, 3 }, };
-
- pci_read_config_word(dev, 0x40, &master_data);
pci_read_config_byte(dev, 0x48, &udma_enable);

if (speed >= XFER_UDMA_0) {
- unsigned int udma = adev->dma_mode - XFER_UDMA_0;
+ unsigned int udma = speed - XFER_UDMA_0;
u16 udma_timing;
u16 ideconf;
int u_clock, u_speed;
@@ -185,46 +186,16 @@ static void it8213_set_dmamode (struct a
ideconf |= u_clock << devid;
pci_write_config_word(dev, 0x54, ideconf);
} else {
- /*
- * MWDMA is driven by the PIO timings. We must also enable
- * IORDY unconditionally along with TIME1. PPE has already
- * been set when the PIO timing was set.
- */
- unsigned int mwdma = adev->dma_mode - XFER_MW_DMA_0;
- unsigned int control;
- u8 slave_data;
+ /* MWDMA is driven by the PIO timings. */
+ unsigned int mwdma = speed - XFER_MW_DMA_0;
static const unsigned int needed_pio[3] = {
XFER_PIO_0, XFER_PIO_3, XFER_PIO_4
};
int pio = needed_pio[mwdma] - XFER_PIO_0;

- control = 3; /* IORDY|TIME1 */
-
- /* If the drive MWDMA is faster than it can do PIO then
- we must force PIO into PIO0 */
+ it8213_set_timings(ap, adev, pio, 1);

- if (adev->pio_mode < needed_pio[mwdma])
- /* Enable DMA timing only */
- control |= 8; /* PIO cycles in PIO0 */
-
- if (devid) { /* Slave */
- master_data &= 0xFF4F; /* Mask out IORDY|TIME1|DMAONLY */
- master_data |= control << 4;
- pci_read_config_byte(dev, 0x44, &slave_data);
- slave_data &= 0xF0;
- /* Load the matching timing */
- slave_data |= ((timings[pio][0] << 2) | timings[pio][1]) << (ap->port_no ? 4 : 0);
- pci_write_config_byte(dev, 0x44, slave_data);
- } else { /* Master */
- master_data &= 0xCCF4; /* Mask out IORDY|TIME1|DMAONLY
- and master timing bits */
- master_data |= control;
- master_data |=
- (timings[pio][0] << 12) |
- (timings[pio][1] << 8);
- }
udma_enable &= ~(1 << devid);
- pci_write_config_word(dev, 0x40, master_data);
}
pci_write_config_byte(dev, 0x48, udma_enable);
}