[PATCH 26/64] alim15x3: fix PIO timings calculations

From: Bartlomiej Zolnierkiewicz
Date: Mon Jan 18 2010 - 12:29:46 EST


From: Bartlomiej Zolnierkiewicz <bzolnier@xxxxxxxxx>
Subject: [PATCH] alim15x3: fix PIO timings calculations

Just use the standard ide_timing_compute() helper to calculate
PIO timings. This fixes many issues with the open-coded version
like potential recovery timings underclocking or not accounting
for the enhanced cycle time specified by the device.

Based on libata pata_ali host driver.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@xxxxxxxxx>
---
drivers/ide/alim15x3.c | 34 +++++++++++++++-------------------
1 file changed, 15 insertions(+), 19 deletions(-)

Index: b/drivers/ide/alim15x3.c
===================================================================
--- a/drivers/ide/alim15x3.c
+++ b/drivers/ide/alim15x3.c
@@ -8,7 +8,7 @@
* Copyright (C) 2002 Alan Cox
* ALi (now ULi M5228) support by Clear Zhang <Clear.Zhang@xxxxxxxxxx>
* Copyright (C) 2007 MontaVista Software, Inc. <source@xxxxxxxxxx>
- * Copyright (C) 2007 Bartlomiej Zolnierkiewicz <bzolnier@xxxxxxxxx>
+ * Copyright (C) 2007-2010 Bartlomiej Zolnierkiewicz
*
* (U)DMA capable version of ali 1533/1543(C), 1535(D)
*
@@ -60,28 +60,22 @@ static void ali_set_pio_mode(ide_drive_t
{
ide_hwif_t *hwif = drive->hwif;
struct pci_dev *dev = to_pci_dev(hwif->dev);
- struct ide_timing *t = ide_timing_find_mode(XFER_PIO_0 + pio);
- int s_time = t->setup, a_time = t->active, c_time = t->cycle;
- u8 s_clc, a_clc, r_clc;
unsigned long flags;
int bus_speed = ide_pci_clk ? ide_pci_clk : 33;
+ unsigned long T = 1000000 / bus_speed; /* PCI clock based */
int port = hwif->channel ? 0x5c : 0x58;
int portFIFO = hwif->channel ? 0x55 : 0x54;
u8 cd_dma_fifo = 0, unit = drive->dn & 1;
+ struct ide_timing t;

- if ((s_clc = (s_time * bus_speed + 999) / 1000) >= 8)
- s_clc = 0;
- if ((a_clc = (a_time * bus_speed + 999) / 1000) >= 8)
- a_clc = 0;
+ ide_timing_compute(drive, XFER_PIO_0 + pio, &t, T, 1);
+
+ t.setup = clamp_val(t.setup, 1, 8) & 7;
+ t.active = clamp_val(t.active, 1, 8) & 7;
+ t.recover = clamp_val(t.recover, 1, 16) & 15;

- if (!(r_clc = (c_time * bus_speed + 999) / 1000 - a_clc - s_clc)) {
- r_clc = 1;
- } else {
- if (r_clc >= 16)
- r_clc = 0;
- }
local_irq_save(flags);
-
+
/*
* PIO mode => ATA FIFO on, ATAPI FIFO off
*/
@@ -99,9 +93,11 @@ static void ali_set_pio_mode(ide_drive_t
pci_write_config_byte(dev, portFIFO, cd_dma_fifo & 0xF0);
}
}
-
- pci_write_config_byte(dev, port, s_clc);
- pci_write_config_byte(dev, port + unit + 2, (a_clc << 4) | r_clc);
+
+ pci_write_config_byte(dev, port, t.setup);
+ pci_write_config_byte(dev, port + unit + 2,
+ (t.active << 4) | t.recover);
+
local_irq_restore(flags);
}

@@ -584,6 +580,6 @@ static void __exit ali15x3_ide_exit(void
module_init(ali15x3_ide_init);
module_exit(ali15x3_ide_exit);

-MODULE_AUTHOR("Michael Aubry, Andrzej Krzysztofowicz, CJ, Andre Hedrick, Alan Cox");
+MODULE_AUTHOR("Michael Aubry, Andrzej Krzysztofowicz, CJ, Andre Hedrick, Alan Cox, Bartlomiej Zolnierkiewicz");
MODULE_DESCRIPTION("PCI driver module for ALi 15x3 IDE");
MODULE_LICENSE("GPL");
--
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