MIPS: MTX-1: fix PCI on the MeshCube and related boards

Add some comments about mtx1_pci_idsel() and remove a dead block of old code.

Signed-off-by Bruno Randolf <[email protected]>

---
 arch/mips/alchemy/mtx-1/board_setup.c |   12 ++++--------
 1 files changed, 4 insertions(+), 8 deletions(-)

(quoted diff) +0 -0

b/arch/mips/alchemy/mtx-1/board_setup.c index 52d883d..3cf2fa2 100644

arch/mips/alchemy/mtx-1/board_setup.c +4 -8

@@ -105,14 +105,10 @@ void __init board_setup(void)
 int
 mtx1_pci_idsel(unsigned int devsel, int assert)
 {
-#define MTX_IDSEL_ONLY_0_AND_3 0
-#if MTX_IDSEL_ONLY_0_AND_3
-	if (devsel != 0 && devsel != 3) {
-		printk(KERN_ERR "*** not 0 or 3\n");
-		return 0;
-	}
-#endif
-
+	/* This function is only necessary to support a proprietary Cardbus
+	 * adapter on the mtx-1 "singleboard" variant. It triggers a custom
+	 * logic chip connected to EXT_IO3 (GPIO1) to suppress IDSEL signals.
+	 */
 	if (assert && devsel != 0)
 		/* Suppress signal to Cardbus */
 		alchemy_gpio_set_value(1, 0);	/* set EXT_IO3 OFF */

This patch fixes a regression introduced by commit "MIPS: Alchemy: MTX-1:
Use linux gpio api." (bb706b28bbd647c2fd7f22d6bf03a18b9552be05) which broke PCI bus operation. The problem is caused by alchemy_gpio2_enable() which resets the GPIO2 block. Two PCI signals (PCI_SERR and PCI_RST) are connected to GPIO2 and they obviously do not to like the reset. Since GPIO2 is correctly initialized by the boot monitor (YAMON) it is not necessary to call this function, so just remove it.

Also replace gpio_set_value() with alchemy_gpio_set_value() to avoid problems in case gpiolib gets initialized after PCI. And since alchemy gpio_set_value() calls au_sync() we don't have to au_sync() again later.

Cc [email protected]

Signed-off-by Bruno Randolf <[email protected]>

---
 arch/mips/alchemy/mtx-1/board_setup.c |    8 +++-----
 1 files changed, 3 insertions(+), 5 deletions(-)

(quoted diff) +0 -0

b/arch/mips/alchemy/mtx-1/board_setup.c index a9f0336..52d883d 100644

arch/mips/alchemy/mtx-1/board_setup.c +3 -5

@@ -67,8 +67,6 @@ static void mtx1_power_off(void)
 
 void __init board_setup(void)
 {
-	alchemy_gpio2_enable();
-
 #if defined(CONFIG_USB_OHCI_HCD) || defined(CONFIG_USB_OHCI_HCD_MODULE)
 	/* Enable USB power switch */
 	alchemy_gpio_direction_output(204, 0);

@@ -117,11 +115,11 @@ mtx1_pci_idsel(unsigned int devsel, int assert)
 
 	if (assert && devsel != 0)
 		/* Suppress signal to Cardbus */
-		gpio_set_value(1, 0);	/* set EXT_IO3 OFF */
+		alchemy_gpio_set_value(1, 0);	/* set EXT_IO3 OFF */
 	else
-		gpio_set_value(1, 1);	/* set EXT_IO3 ON */
+		alchemy_gpio_set_value(1, 1);	/* set EXT_IO3 ON */
 
-	au_sync_udelay(1);
+	udelay(1);
 	return 1;
 }

Cc [email protected]