ide: add CS5536 host driver (v3)
This is a port of libata's pata_cs5536.c (written by Martin K. Petersen)
to IDE subsystem.
Changes done while at it:
* Reprogram PIO/MWDMA timings if needed before and after DMA transfer
(chipset uses shared PIO/MWDMA timings).
* Fix cable detection to report 80-wires cable if BIOS set it for any
device on a port (IDE core will do drive-side cable detection later).
* Don't disable UDMA while programming PIO timings.
* Simplify PCI/MSR support.
Pros of having IDE host driver in addition to libata's one:
* IDE is much lighter than SCSI+libata, the host driver itself is also
a bit smaller:
text data bss dec hex filename
1261 496 4 1761 6e1 drivers/ata/pata_cs5536.o
1242 128 4 1374 55e drivers/ide/cs5536.o
* This allows use of IDE features which are unavailable under libata.
v2:
* Fixes per review from Sergei:
- simplify dependency check in Kconfig
- use IDE_DRV_MASK also for ->drive_data
- disable UDMA when programming MWDMA
- program new DTC timings only when necessary
- fix printk() level in cs5536_init_one()
* Fix patch description according to comments from Alan and Sergei.
v3:
* Smarter masking of UDMA bits per Sergei's suggestion.
Cc: Martin K. Petersen <mkp@mkp.net>
Cc: Karl Auerbach <karl@iwl.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/cs5536.c b/drivers/ide/cs5536.c
new file mode 100644
index 0000000..7a62db7
--- /dev/null
+++ b/drivers/ide/cs5536.c
@@ -0,0 +1,308 @@
+/*
+ * CS5536 PATA support
+ * (C) 2007 Martin K. Petersen <mkp@mkp.net>
+ * (C) 2009 Bartlomiej Zolnierkiewicz
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Documentation:
+ * Available from AMD web site.
+ *
+ * The IDE timing registers for the CS5536 live in the Geode Machine
+ * Specific Register file and not PCI config space. Most BIOSes
+ * virtualize the PCI registers so the chip looks like a standard IDE
+ * controller. Unfortunately not all implementations get this right.
+ * In particular some have problems with unaligned accesses to the
+ * virtualized PCI registers. This driver always does full dword
+ * writes to work around the issue. Also, in case of a bad BIOS this
+ * driver can be loaded with the "msr=1" parameter which forces using
+ * the Machine Specific Registers to configure the device.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/ide.h>
+#include <asm/msr.h>
+
+#define DRV_NAME "cs5536"
+
+enum {
+ MSR_IDE_CFG = 0x51300010,
+ PCI_IDE_CFG = 0x40,
+
+ CFG = 0,
+ DTC = 2,
+ CAST = 3,
+ ETC = 4,
+
+ IDE_CFG_CHANEN = (1 << 1),
+ IDE_CFG_CABLE = (1 << 17) | (1 << 16),
+
+ IDE_D0_SHIFT = 24,
+ IDE_D1_SHIFT = 16,
+ IDE_DRV_MASK = 0xff,
+
+ IDE_CAST_D0_SHIFT = 6,
+ IDE_CAST_D1_SHIFT = 4,
+ IDE_CAST_DRV_MASK = 0x3,
+
+ IDE_CAST_CMD_SHIFT = 24,
+ IDE_CAST_CMD_MASK = 0xff,
+
+ IDE_ETC_UDMA_MASK = 0xc0,
+};
+
+static int use_msr;
+
+static int cs5536_read(struct pci_dev *pdev, int reg, u32 *val)
+{
+ if (unlikely(use_msr)) {
+ u32 dummy;
+
+ rdmsr(MSR_IDE_CFG + reg, *val, dummy);
+ return 0;
+ }
+
+ return pci_read_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
+}
+
+static int cs5536_write(struct pci_dev *pdev, int reg, int val)
+{
+ if (unlikely(use_msr)) {
+ wrmsr(MSR_IDE_CFG + reg, val, 0);
+ return 0;
+ }
+
+ return pci_write_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
+}
+
+static void cs5536_program_dtc(ide_drive_t *drive, u8 tim)
+{
+ struct pci_dev *pdev = to_pci_dev(drive->hwif->dev);
+ int dshift = (drive->dn & 1) ? IDE_D1_SHIFT : IDE_D0_SHIFT;
+ u32 dtc;
+
+ cs5536_read(pdev, DTC, &dtc);
+ dtc &= ~(IDE_DRV_MASK << dshift);
+ dtc |= tim << dshift;
+ cs5536_write(pdev, DTC, dtc);
+}
+
+/**
+ * cs5536_cable_detect - detect cable type
+ * @hwif: Port to detect on
+ *
+ * Perform cable detection for ATA66 capable cable.
+ *
+ * Returns a cable type.
+ */
+
+static u8 cs5536_cable_detect(ide_hwif_t *hwif)
+{
+ struct pci_dev *pdev = to_pci_dev(hwif->dev);
+ u32 cfg;
+
+ cs5536_read(pdev, CFG, &cfg);
+
+ if (cfg & IDE_CFG_CABLE)
+ return ATA_CBL_PATA80;
+ else
+ return ATA_CBL_PATA40;
+}
+
+/**
+ * cs5536_set_pio_mode - PIO timing setup
+ * @drive: ATA device
+ * @pio: PIO mode number
+ */
+
+static void cs5536_set_pio_mode(ide_drive_t *drive, const u8 pio)
+{
+ static const u8 drv_timings[5] = {
+ 0x98, 0x55, 0x32, 0x21, 0x20,
+ };
+
+ static const u8 addr_timings[5] = {
+ 0x2, 0x1, 0x0, 0x0, 0x0,
+ };
+
+ static const u8 cmd_timings[5] = {
+ 0x99, 0x92, 0x90, 0x22, 0x20,
+ };
+
+ struct pci_dev *pdev = to_pci_dev(drive->hwif->dev);
+ ide_drive_t *pair = ide_get_pair_dev(drive);
+ int cshift = (drive->dn & 1) ? IDE_CAST_D1_SHIFT : IDE_CAST_D0_SHIFT;
+ u32 cast;
+ u8 cmd_pio = pio;
+
+ if (pair)
+ cmd_pio = min(pio, ide_get_best_pio_mode(pair, 255, 4));
+
+ drive->drive_data &= (IDE_DRV_MASK << 8);
+ drive->drive_data |= drv_timings[pio];
+
+ cs5536_program_dtc(drive, drv_timings[pio]);
+
+ cs5536_read(pdev, CAST, &cast);
+
+ cast &= ~(IDE_CAST_DRV_MASK << cshift);
+ cast |= addr_timings[pio] << cshift;
+
+ cast &= ~(IDE_CAST_CMD_MASK << IDE_CAST_CMD_SHIFT);
+ cast |= cmd_timings[cmd_pio] << IDE_CAST_CMD_SHIFT;
+
+ cs5536_write(pdev, CAST, cast);
+}
+
+/**
+ * cs5536_set_dma_mode - DMA timing setup
+ * @drive: ATA device
+ * @mode: DMA mode
+ */
+
+static void cs5536_set_dma_mode(ide_drive_t *drive, const u8 mode)
+{
+ static const u8 udma_timings[6] = {
+ 0xc2, 0xc1, 0xc0, 0xc4, 0xc5, 0xc6,
+ };
+
+ static const u8 mwdma_timings[3] = {
+ 0x67, 0x21, 0x20,
+ };
+
+ struct pci_dev *pdev = to_pci_dev(drive->hwif->dev);
+ int dshift = (drive->dn & 1) ? IDE_D1_SHIFT : IDE_D0_SHIFT;
+ u32 etc;
+
+ cs5536_read(pdev, ETC, &etc);
+
+ if (mode >= XFER_UDMA_0) {
+ etc &= ~(IDE_DRV_MASK << dshift);
+ etc |= udma_timings[mode - XFER_UDMA_0] << dshift;
+ } else { /* MWDMA */
+ etc &= ~(IDE_ETC_UDMA_MASK << dshift);
+ drive->drive_data &= IDE_DRV_MASK;
+ drive->drive_data |= mwdma_timings[mode - XFER_MW_DMA_0] << 8;
+ }
+
+ cs5536_write(pdev, ETC, etc);
+}
+
+static void cs5536_dma_start(ide_drive_t *drive)
+{
+ if (drive->current_speed < XFER_UDMA_0 &&
+ (drive->drive_data >> 8) != (drive->drive_data & IDE_DRV_MASK))
+ cs5536_program_dtc(drive, drive->drive_data >> 8);
+
+ ide_dma_start(drive);
+}
+
+static int cs5536_dma_end(ide_drive_t *drive)
+{
+ int ret = ide_dma_end(drive);
+
+ if (drive->current_speed < XFER_UDMA_0 &&
+ (drive->drive_data >> 8) != (drive->drive_data & IDE_DRV_MASK))
+ cs5536_program_dtc(drive, drive->drive_data & IDE_DRV_MASK);
+
+ return ret;
+}
+
+static const struct ide_port_ops cs5536_port_ops = {
+ .set_pio_mode = cs5536_set_pio_mode,
+ .set_dma_mode = cs5536_set_dma_mode,
+ .cable_detect = cs5536_cable_detect,
+};
+
+static const struct ide_dma_ops cs5536_dma_ops = {
+ .dma_host_set = ide_dma_host_set,
+ .dma_setup = ide_dma_setup,
+ .dma_exec_cmd = ide_dma_exec_cmd,
+ .dma_start = cs5536_dma_start,
+ .dma_end = cs5536_dma_end,
+ .dma_test_irq = ide_dma_test_irq,
+ .dma_lost_irq = ide_dma_lost_irq,
+ .dma_timeout = ide_dma_timeout,
+};
+
+static const struct ide_port_info cs5536_info = {
+ .name = DRV_NAME,
+ .port_ops = &cs5536_port_ops,
+ .dma_ops = &cs5536_dma_ops,
+ .host_flags = IDE_HFLAG_SINGLE,
+ .pio_mask = ATA_PIO4,
+ .mwdma_mask = ATA_MWDMA2,
+ .udma_mask = ATA_UDMA5,
+};
+
+/**
+ * cs5536_init_one
+ * @dev: PCI device
+ * @id: Entry in match table
+ */
+
+static int cs5536_init_one(struct pci_dev *dev, const struct pci_device_id *id)
+{
+ u32 cfg;
+
+ if (use_msr)
+ printk(KERN_INFO DRV_NAME ": Using MSR regs instead of PCI\n");
+
+ cs5536_read(dev, CFG, &cfg);
+
+ if ((cfg & IDE_CFG_CHANEN) == 0) {
+ printk(KERN_ERR DRV_NAME ": disabled by BIOS\n");
+ return -ENODEV;
+ }
+
+ return ide_pci_init_one(dev, &cs5536_info, NULL);
+}
+
+static const struct pci_device_id cs5536_pci_tbl[] = {
+ { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_CS5536_IDE), },
+ { },
+};
+
+static struct pci_driver cs5536_pci_driver = {
+ .name = DRV_NAME,
+ .id_table = cs5536_pci_tbl,
+ .probe = cs5536_init_one,
+ .remove = ide_pci_remove,
+ .suspend = ide_pci_suspend,
+ .resume = ide_pci_resume,
+};
+
+static int __init cs5536_init(void)
+{
+ return pci_register_driver(&cs5536_pci_driver);
+}
+
+static void __exit cs5536_exit(void)
+{
+ pci_unregister_driver(&cs5536_pci_driver);
+}
+
+MODULE_AUTHOR("Martin K. Petersen, Bartlomiej Zolnierkiewicz");
+MODULE_DESCRIPTION("low-level driver for the CS5536 IDE controller");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(pci, cs5536_pci_tbl);
+
+module_param_named(msr, use_msr, int, 0644);
+MODULE_PARM_DESC(msr, "Force using MSR to configure IDE function (Default: 0)");
+
+module_init(cs5536_init);
+module_exit(cs5536_exit);