Hello. On 13-10-2011 17:39, Bartlomiej Zolnierkiewicz wrote:
From: Bartlomiej Zolnierkiewicz<bzolnier@xxxxxxxxx> Subject: [PATCH v2] 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<bzolnier@xxxxxxxxx>
I'm still inclined to NAK this patch.
--- v2: remove use_mwdma variable and fix comment style
earlier references: https://lkml.org/lkml/2011/2/8/99 drivers/ata/ata_piix.c | 111 ++++++++++++++++--------------------------------- 1 file changed, 38 insertions(+), 73 deletions(-)
Index: b/drivers/ata/ata_piix.c =================================================================== --- a/drivers/ata/ata_piix.c +++ b/drivers/ata/ata_piix.c
[...]
@@ -811,31 +822,20 @@ static void do_pata_set_dmamode(struct a
[...]
- if (ap->udma_mask) - pci_read_config_byte(dev, 0x48,&udma_enable);
Don't think you should remove this.
- 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);
But you should also clear the UDMA enable bit when setting an MWDMA mode, no?
+ /* * UDMA is handled by a combination of clock switching and * selection of dividers @@ -868,56 +868,21 @@ static void do_pata_set_dmamode(struct a 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;
[...]
- if (ap->udma_mask) - udma_enable&= ~(1<< devid);
Still don't understand why you're removing this code.
- - pci_write_config_word(dev, master_port, master_data); + /* XFER_PIO_0 is never used currently */ + piix_set_timings(ap, adev, pio); } - /* Don't scribble on 0x48 if the controller does not support UDMA */ - if (ap->udma_mask) - pci_write_config_byte(dev, 0x48, udma_enable);
Should have kept this one too... MBR, Sergei -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html