[PATCH v2] m68k: amiga: config: upon boot, turn off all incoming interrupts from the Warp1260

[Paolo Pisati <p.pisati@gmail.com>]

Amiga 1200 boot crashes in local_irq_enable() (or auto_irq_enable()) with an
interrupt storm (the Warp1260 board interrupts appear to still be active at boot
time): CS-Lab told me where to find the interrupt register (and its layout) so
here's patch that turns off all incoming interrupts during
config.c::amiga_parse_bootinfo().

Changes since v1:
-addressed all comments from Geert and Michael

Link: https://lore.kernel.org/r/ZkjwzVwYeQtyAPrL@amaterasu.local
Cc: stable <stable@kernel.org>
Signed-off-by: Paolo Pisati <p.pisati@gmail.com>
---
 arch/m68k/amiga/config.c       | 9 +++++++++
 include/uapi/linux/zorro_ids.h | 3 +++
 2 files changed, 12 insertions(+)

diff --git a/arch/m68k/amiga/config.c b/arch/m68k/amiga/config.c
index 3137b45750df..fa74452600c1 100644
--- a/arch/m68k/amiga/config.c
+++ b/arch/m68k/amiga/config.c
@@ -180,6 +180,15 @@ int __init amiga_parse_bootinfo(const struct bi_record *record)
 			dev->slotsize = be16_to_cpu(cd->cd_SlotSize);
 			dev->boardaddr = be32_to_cpu(cd->cd_BoardAddr);
 			dev->boardsize = be32_to_cpu(cd->cd_BoardSize);
+
+			/* CS-LAB Warp 1260 workaround */
+			if (be16_to_cpu(dev->rom.er_Manufacturer) == ZORRO_MANUF(ZORRO_PROD_CSLAB_WARP_1260) &&
+			    dev->rom.er_Product == ZORRO_PROD(ZORRO_PROD_CSLAB_WARP_1260)) {
+
+				/* turn off all interrupts */
+				pr_info("Warp 1260 card detected: applying interrupt storm workaround");
+				*(uint32_t *)(dev->boardaddr + 0x1000) = 0x0FFF;
+			}
 		} else
 			pr_warn("amiga_parse_bootinfo: too many AutoConfig devices\n");
 #endif /* CONFIG_ZORRO */
diff --git a/include/uapi/linux/zorro_ids.h b/include/uapi/linux/zorro_ids.h
index 6e574d7b7d79..393f2ee9c042 100644
--- a/include/uapi/linux/zorro_ids.h
+++ b/include/uapi/linux/zorro_ids.h
@@ -449,6 +449,9 @@
 #define  ZORRO_PROD_VMC_ISDN_BLASTER_Z2				ZORRO_ID(VMC, 0x01, 0)
 #define  ZORRO_PROD_VMC_HYPERCOM_4				ZORRO_ID(VMC, 0x02, 0)
 
+#define ZORRO_MANUF_CSLAB					0x1400
+#define  ZORRO_PROD_CSLAB_WARP_1260				ZORRO_ID(CSLAB, 0x65, 0)
+
 #define ZORRO_MANUF_INFORMATION					0x157C
 #define  ZORRO_PROD_INFORMATION_ISDN_ENGINE_I			ZORRO_ID(INFORMATION, 0x64, 0)
 
-- 
2.34.1