Re: [RFC] [Patch] pata_cs5536: add quirk for broken udma

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 07/26/2012 09:40 AM, Christian Gmeiner wrote:
Hi all.

I am working on a device which uses the cs5536 pata driver. There are
some broken hardware
revisions out in the field, which can be detected via DMI. I am
looking for a way now to get
this quirk upstream. On older versions with an embedded BIOS and I
used libata.dma=0
to disable dma completely.
Now we are switching to a coreboot/seabios based BIOS where we have
DMI support and
so I think its a good idea to get rid of all those hacky kernel
parameters as the same image
is used other devices where libata.dma=0 is not so a good idea.

I came up with this patch. I am not sure if it would be better to
patch libata-core.c

Thanks,
---
Christian Gmeiner, MSc


--- linux-3.2.24___OK/drivers/ata/pata_cs5536.c	2012-07-25
05:11:50.000000000 +0200
+++ linux-3.2.24/drivers/ata/pata_cs5536.c	2012-07-26 15:38:27.674909884 +0200
@@ -37,6 +37,7 @@
  #include <linux/delay.h>
  #include <linux/libata.h>
  #include <scsi/scsi_host.h>
+#include <linux/dmi.h>

  #ifdef CONFIG_X86_32
  #include <asm/msr.h>
@@ -95,6 +96,21 @@
  	PCI_IDE_CFG, PCI_IDE_DTC, PCI_IDE_CAST, PCI_IDE_ETC,
  };

+/* Some Bachmann OT200 devices have a non working UDMA support due a
+ * missing resistor.
+ */
+static const struct dmi_system_id udma_quirk_dmi_table[] = {
+        {
+                .ident = "Bachmann electronic OT200",
+                .matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Bachmann electronic"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "OT200"),
+			DMI_MATCH(DMI_PRODUCT_VERSION, "1")
+		},
+        },
+        { }
+};
+
  static inline int cs5536_read(struct pci_dev *pdev, int reg, u32 *val)
  {
  	if (unlikely(use_msr)) {
@@ -257,9 +273,22 @@
  		.port_ops = &cs5536_port_ops,
  	};

-	const struct ata_port_info *ppi[] = { &info, &ata_dummy_port_info };
+	static const struct ata_port_info no_udma_info = {
+                .flags = ATA_FLAG_SLAVE_POSS,
+                .pio_mask = ATA_PIO4,
+                .port_ops = &cs5536_port_ops,
+	};
+
+	const struct ata_port_info *ppi[2];
  	u32 cfg;

+	if (dmi_check_system(udma_quirk_dmi_table))
+		ppi[0] = &no_udma_info;
+	else
+		ppi[0] = &info;
+
+	ppi[1] = &ata_dummy_port_info;

ACK patch content, but it did not apply



--
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


[Index of Archives]     [Linux Filesystems]     [Linux SCSI]     [Linux RAID]     [Git]     [Kernel Newbies]     [Linux Newbie]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Samba]     [Device Mapper]

  Powered by Linux