From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bartlomiej Zolnierkiewicz Subject: [PATCH 02/20] ata_piix: unify code for programming PIO and MWDMA timings Date: Tue, 08 Feb 2011 13:23:46 +0100 Message-ID: <20110208122346.19110.8441.sendpatchset@linux-mhg7.site> References: <20110208122314.19110.4092.sendpatchset@linux-mhg7.site> Return-path: In-Reply-To: <20110208122314.19110.4092.sendpatchset@linux-mhg7.site> Sender: linux-kernel-owner@vger.kernel.org To: linux-ide@vger.kernel.org Cc: Bartlomiej Zolnierkiewicz , linux-kernel@vger.kernel.org List-Id: linux-ide@vger.kernel.org >>From ca6c1fbc7d853829524b87a3bcbbb1f67796281c Mon Sep 17 00:00:00 2001 From: Bartlomiej Zolnierkiewicz Date: Tue, 8 Feb 2011 12:39:24 +0100 Subject: [PATCH 02/20] ata_piix: unify code for programming PIO and MWDMA timings Besides making things noticably simpler it results in ~2% decrease in the driver LOC count and also ~2% decrease in the driver binary size (as measured on x86-32). Fix piix_set_piomode() documentation while at it. Signed-off-by: Bartlomiej Zolnierkiewicz --- drivers/ata/ata_piix.c | 112 ++++++++++++++++-------------------------------- 1 files changed, 37 insertions(+), 75 deletions(-) diff --git a/drivers/ata/ata_piix.c b/drivers/ata/ata_piix.c index 0f4856d..c954f91 100644 --- a/drivers/ata/ata_piix.c +++ b/drivers/ata/ata_piix.c @@ -696,22 +696,11 @@ static int piix_pata_prereset(struct ata_link *link, unsigned long deadline) static DEFINE_SPINLOCK(piix_lock); -/** - * piix_set_piomode - Initialize host controller PATA PIO timings - * @ap: Port whose timings we are configuring - * @adev: um - * - * Set PIO mode for device, in host controller PCI config space. - * - * LOCKING: - * None (inherited from caller). - */ - -static void piix_set_piomode(struct ata_port *ap, struct ata_device *adev) +static void piix_set_timings(struct ata_port *ap, struct ata_device *adev, + u8 pio, bool use_mwdma) { struct pci_dev *dev = to_pci_dev(ap->host->dev); unsigned long flags; - unsigned int pio = adev->pio_mode - XFER_PIO_0; unsigned int is_slave = (adev->devno != 0); unsigned int master_port= ap->port_no ? 0x42 : 0x40; unsigned int slave_port = 0x44; @@ -732,14 +721,18 @@ static void piix_set_piomode(struct ata_port *ap, struct ata_device *adev) { 2, 1 }, { 2, 3 }, }; - if (pio >= 2) + if (pio >= 2 || use_mwdma) control |= 1; /* TIME1 enable */ - if (ata_pio_need_iordy(adev)) + if (ata_pio_need_iordy(adev) || use_mwdma) control |= 2; /* IE enable */ - /* Intel specifies that the PPE functionality is for disk only */ if (adev->class == ATA_DEV_ATA) control |= 4; /* PPE enable */ + /* 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 */ spin_lock_irqsave(&piix_lock, flags); @@ -788,6 +781,22 @@ static void piix_set_piomode(struct ata_port *ap, struct ata_device *adev) } /** + * piix_set_piomode - Initialize host controller PATA PIO timings + * @ap: Port whose timings we are configuring + * @adev: Drive in question + * + * Set PIO mode for device, in host controller PCI config space. + * + * LOCKING: + * None (inherited from caller). + */ + +static void piix_set_piomode(struct ata_port *ap, struct ata_device *adev) +{ + piix_set_timings(ap, adev, adev->pio_mode - XFER_PIO_0, 0); +} + +/** * do_pata_set_dmamode - Initialize host controller PATA PIO timings * @ap: Port whose timings we are configuring * @adev: Drive in question @@ -803,31 +812,20 @@ static void do_pata_set_dmamode(struct ata_port *ap, struct ata_device *adev, in { struct pci_dev *dev = to_pci_dev(ap->host->dev); unsigned long flags; - u8 master_port = ap->port_no ? 0x42 : 0x40; - u16 master_data; u8 speed = adev->dma_mode; int devid = adev->devno + 2 * ap->port_no; u8 udma_enable = 0; - static const /* ISP RTC */ - u8 timings[][2] = { { 0, 0 }, - { 0, 0 }, - { 1, 0 }, - { 2, 1 }, - { 2, 3 }, }; - - spin_lock_irqsave(&piix_lock, flags); - - pci_read_config_word(dev, master_port, &master_data); - if (ap->udma_mask) - 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; + spin_lock_irqsave(&piix_lock, flags); + + pci_read_config_byte(dev, 0x48, &udma_enable); + /* * UDMA is handled by a combination of clock switching and * selection of dividers @@ -860,56 +858,20 @@ static void do_pata_set_dmamode(struct ata_port *ap, struct ata_device *adev, in performance (WR_PingPong_En) */ pci_write_config_word(dev, 0x54, ideconf); } + + pci_write_config_byte(dev, 0x48, udma_enable); + + spin_unlock_irqrestore(&piix_lock, flags); } 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; 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 */ - - if (adev->pio_mode < needed_pio[mwdma]) - /* Enable DMA timing only */ - control |= 8; /* PIO cycles in PIO0 */ - - if (adev->devno) { /* Slave */ - master_data &= 0xFF4F; /* Mask out IORDY|TIME1|DMAONLY */ - master_data |= control << 4; - pci_read_config_byte(dev, 0x44, &slave_data); - slave_data &= (ap->port_no ? 0x0f : 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); - } - - if (ap->udma_mask) - udma_enable &= ~(1 << devid); - - pci_write_config_word(dev, master_port, master_data); + piix_set_timings(ap, adev, pio, 1); } - /* Don't scribble on 0x48 if the controller does not support UDMA */ - if (ap->udma_mask) - pci_write_config_byte(dev, 0x48, udma_enable); - - spin_unlock_irqrestore(&piix_lock, flags); } /** -- 1.7.1