[U-Boot] [PATCHv2 2/2] mucmc52, uc101: delete ata at 3a00 node, if no CF card is detected

[Heiko Schocher]

U-Boot can detect, if a ide device is present or not.
If not and this new config option is activated, u-boot
removes the ata node from the DTS before booting Linux,
so the Linux IDE driver didn;t crashs, when probing the
device. This is needed for buggy hardware (uc101) where
no pull down resistor is connected to the signal IDE5V_DD7.

Signed-off-by: Heiko Schocher <hs at denx.de>
---
changes since v1:
- added comment from Wolfgang Denk, to move this to a more
  common place, so others can also use it, and made it
  therefore per CONFIG_OF_IDE_FIXUP selectable.

 README            |    9 +++++++++
 cpu/mpc5xxx/cpu.c |   18 ++++++++++++++++++
 2 files changed, 27 insertions(+), 0 deletions(-)

diff --git a/README b/README
index ff4ed8b..b9364bf 100644
--- a/README
+++ b/README
@@ -386,6 +386,15 @@ The following options need to be configured:
 		This define fills in the correct boot CPU in the boot
 		param header, the default value is zero if undefined.

+		CONFIG_OF_IDE_FIXUP
+
+		U-Boot can detect, if a ide device is present or not.
+		If not and this config option is activated, u-boot
+		removes the ata node from the DTS before booting Linux,
+		so the Linux IDE driver didn;t crashs, when probing the
+		device. This is needed for buggy hardware (uc101) where
+		no pull down resistor is connected to the signal IDE5V_DD7.
+
 - vxWorks boot parameters:

 		bootvx constructs a valid bootline using the following
diff --git a/cpu/mpc5xxx/cpu.c b/cpu/mpc5xxx/cpu.c
index f6258c7..a2fc323 100644
--- a/cpu/mpc5xxx/cpu.c
+++ b/cpu/mpc5xxx/cpu.c
@@ -125,6 +125,9 @@ void ft_cpu_setup(void *blob, bd_t *bd)
 	uchar enetaddr[6];
 	char * eth_path = "/" OF_SOC "/ethernet at 3000";
 #endif
+#if defined(CONFIG_OF_IDE_FIXUP)
+	extern block_dev_desc_t ide_dev_desc[CONFIG_SYS_IDE_MAXDEVICE];
+#endif

 	do_fixup_by_path_u32(blob, cpu_path, "timebase-frequency", OF_TBCLK, 1);
 	do_fixup_by_path_u32(blob, cpu_path, "bus-frequency", bd->bi_busfreq, 1);
@@ -137,6 +140,21 @@ void ft_cpu_setup(void *blob, bd_t *bd)
 	do_fixup_by_path(blob, eth_path, "mac-address", enetaddr, 6, 0);
 	do_fixup_by_path(blob, eth_path, "local-mac-address", enetaddr, 6, 0);
 #endif
+#if defined(CONFIG_OF_IDE_FIXUP)
+	if (ide_dev_desc[0].type == DEV_TYPE_UNKNOWN) {
+		/* NO CF card detected -> delete ata node in DTS */
+		int nodeoffset = 0;
+		char nodename[] = "/soc5200 at f0000000/ata at 3a00";
+
+		nodeoffset = fdt_path_offset (blob, nodename);
+		if (nodeoffset >= 0) {
+			fdt_del_node(blob, nodeoffset);
+		} else
+			printf("%s: cannot find %s node err:%s\n",
+				__func__, nodename, fdt_strerror(nodeoffset));
+	}
+
+#endif
 }
 #endif

-- 
1.6.0.6