From 0361c7e504b1fa3c2901643088e2f29c0354ab31 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <arnd@arndb.de>
Date: Fri, 1 Apr 2022 15:58:09 +0200
Subject: ARM: ep93xx: multiplatform support

With the clock support and the interrupts out of the way, ep93xx can be
compiled into the same kernel image as the other ARMv4/v5 platforms. The
last obstacle are the two workarounds for broken boot loaders that
require us to re-initialize the ethernet controller and/or the watchdog
on certain machines.

Move this code into the decompressor sources directly, checking for
each possibly affected machine individually.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 arch/arm/boot/compressed/misc-ep93xx.h | 86 ++++++++++++++++++++++++++++++++++
 arch/arm/boot/compressed/misc.c        |  4 ++
 2 files changed, 90 insertions(+)
 create mode 100644 arch/arm/boot/compressed/misc-ep93xx.h

(limited to 'arch/arm/boot/compressed')

diff --git a/arch/arm/boot/compressed/misc-ep93xx.h b/arch/arm/boot/compressed/misc-ep93xx.h
new file mode 100644
index 000000000000..3dc942589cba
--- /dev/null
+++ b/arch/arm/boot/compressed/misc-ep93xx.h
@@ -0,0 +1,86 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
+ */
+
+#include <asm/mach-types.h>
+
+static inline unsigned int __raw_readl(unsigned int ptr)
+{
+	return *((volatile unsigned int *)ptr);
+}
+
+static inline void __raw_writeb(unsigned char value, unsigned int ptr)
+{
+	*((volatile unsigned char *)ptr) = value;
+}
+
+static inline void __raw_writel(unsigned int value, unsigned int ptr)
+{
+	*((volatile unsigned int *)ptr) = value;
+}
+
+/*
+ * Some bootloaders don't turn off DMA from the ethernet MAC before
+ * jumping to linux, which means that we might end up with bits of RX
+ * status and packet data scribbled over the uncompressed kernel image.
+ * Work around this by resetting the ethernet MAC before we uncompress.
+ */
+#define PHYS_ETH_SELF_CTL		0x80010020
+#define ETH_SELF_CTL_RESET		0x00000001
+
+static inline void ep93xx_ethernet_reset(void)
+{
+	unsigned int v;
+
+	/* Reset the ethernet MAC.  */
+	v = __raw_readl(PHYS_ETH_SELF_CTL);
+	__raw_writel(v | ETH_SELF_CTL_RESET, PHYS_ETH_SELF_CTL);
+
+	/* Wait for reset to finish.  */
+	while (__raw_readl(PHYS_ETH_SELF_CTL) & ETH_SELF_CTL_RESET)
+		;
+}
+
+#define TS72XX_WDT_CONTROL_PHYS_BASE	0x23800000
+#define TS72XX_WDT_FEED_PHYS_BASE	0x23c00000
+#define TS72XX_WDT_FEED_VAL		0x05
+
+static inline void __maybe_unused ts72xx_watchdog_disable(void)
+{
+	__raw_writeb(TS72XX_WDT_FEED_VAL, TS72XX_WDT_FEED_PHYS_BASE);
+	__raw_writeb(0, TS72XX_WDT_CONTROL_PHYS_BASE);
+}
+
+static inline void ep93xx_decomp_setup(void)
+{
+	if (machine_is_ts72xx())
+		ts72xx_watchdog_disable();
+
+	if (machine_is_adssphere() ||
+	    machine_is_edb9301() ||
+	    machine_is_edb9302() ||
+	    machine_is_edb9302a() ||
+	    machine_is_edb9302a() ||
+	    machine_is_edb9307() ||
+	    machine_is_edb9307a() ||
+	    machine_is_edb9307a() ||
+	    machine_is_edb9312() ||
+	    machine_is_edb9315() ||
+	    machine_is_edb9315a() ||
+	    machine_is_edb9315a() ||
+	    machine_is_gesbc9312() ||
+	    machine_is_micro9() ||
+	    machine_is_micro9l() ||
+	    machine_is_micro9m() ||
+	    machine_is_micro9s() ||
+	    machine_is_micro9m() ||
+	    machine_is_micro9l() ||
+	    machine_is_micro9s() ||
+	    machine_is_sim_one() ||
+	    machine_is_snapper_cl15() ||
+	    machine_is_ts72xx() ||
+	    machine_is_bk3() ||
+	    machine_is_vision_ep9307())
+		ep93xx_ethernet_reset();
+}
diff --git a/arch/arm/boot/compressed/misc.c b/arch/arm/boot/compressed/misc.c
index c3c66ff2d696..cb2e069dc73f 100644
--- a/arch/arm/boot/compressed/misc.c
+++ b/arch/arm/boot/compressed/misc.c
@@ -23,6 +23,7 @@ unsigned int __machine_arch_type;
 #include <linux/types.h>
 #include <linux/linkage.h>
 #include "misc.h"
+#include "misc-ep93xx.h"
 
 static void putstr(const char *ptr);
 
@@ -143,6 +144,9 @@ decompress_kernel(unsigned long output_start, unsigned long free_mem_ptr_p,
 	free_mem_end_ptr	= free_mem_ptr_end_p;
 	__machine_arch_type	= arch_id;
 
+#ifdef CONFIG_ARCH_EP93XX
+	ep93xx_decomp_setup();
+#endif
 	arch_decomp_setup();
 
 	putstr("Uncompressing Linux...");
-- 
cgit