Segher Boessenkool wrote:

You set up DBAT1 here...

quoted

+setup_usbgecko_bat:
+    /* prepare a BAT for early io */
+    lis    r8, 0x0c00
+    ori    r8, r8, 0x002a    /* uncached, guarded ,rw */
+    lis    r11, 0xcc00
+    ori    r11, r11, 0x3    /* 128K */
+#ifdef CONFIG_WII
+    oris    r8, r8, 0x0100
+    oris    r11, r11, 0x0100
+#endif
+    mtspr    SPRN_DBAT1L, r8
+    mtspr    SPRN_DBAT1U, r11
+    sync
+    isync
+    blr

... and again here:

quoted

+void __init udbg_init_usbgecko(void)
+{
+    unsigned long vaddr, paddr;
+
+#if defined(CONFIG_GAMECUBE)
+    paddr = 0x0c000000;
+#elif defined(CONFIG_WII)
+    paddr = 0x0d000000;
+#else
+#error Invalid platform for USB Gecko based early debugging.
+#endif
+
+    vaddr = 0xc0000000 | paddr;
+    setbat(1, vaddr, paddr, 128*1024, PAGE_KERNEL_NCG);

Do you need to do it twice?

Uhmm... I need to re-check it.
IIRC the BATs were re-initialized in between. But I'm not sure now :)

quoted

+    ug_io_base = (void __iomem *)(vaddr | 0x6814);

Oh, hardcoded slot2, now i'm confused which one should be it :-)

early udbg  : hardcoded to mem2 slot
normal udbg : as specified in device tree

Clearer now ? ;)

Thanks for the review!
Albert