--- zzzz-none-000/linux-3.10.107/arch/mips/include/asm/mach-malta/kernel-entry-init.h	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/mips/include/asm/mach-malta/kernel-entry-init.h	2021-02-04 17:41:59.000000000 +0000
@@ -5,27 +5,115 @@
  *
  * Chris Dearman (chris@mips.com)
  * Copyright (C) 2007 Mips Technologies, Inc.
+ * Copyright (C) 2014 Imagination Technologies Ltd.
  */
 #ifndef __ASM_MACH_MIPS_KERNEL_ENTRY_INIT_H
 #define __ASM_MACH_MIPS_KERNEL_ENTRY_INIT_H
 
+#include <asm/regdef.h>
+#include <asm/mipsregs.h>
+
+	/*
+	 * Prepare segments for EVA boot:
+	 *
+	 * This is in case the processor boots in legacy configuration
+	 * (SI_EVAReset is de-asserted and CONFIG5.K == 0)
+	 *
+	 * ========================= Mappings =============================
+	 * Virtual memory           Physical memory           Mapping
+	 * 0x00000000 - 0x7fffffff  0x80000000 - 0xfffffffff   MUSUK (kuseg)
+	 *                          Flat 2GB physical memory
+	 *
+	 * 0x80000000 - 0x9fffffff  0x00000000 - 0x1ffffffff   MUSUK (kseg0)
+	 * 0xa0000000 - 0xbf000000  0x00000000 - 0x1ffffffff   MUSUK (kseg1)
+	 * 0xc0000000 - 0xdfffffff             -                 MK  (kseg2)
+	 * 0xe0000000 - 0xffffffff             -                 MK  (kseg3)
+	 *
+	 *
+	 * Lowmem is expanded to 2GB
+	 *
+	 * The following code uses the t0, t1, t2 and ra registers without
+	 * previously preserving them.
+	 *
+	 */
+	.macro	platform_eva_init
+
+	.set	push
+	.set	reorder
+	/*
+	 * Get Config.K0 value and use it to program
+	 * the segmentation registers
+	 */
+	mfc0    t1, CP0_CONFIG
+	andi	t1, 0x7 /* CCA */
+	move	t2, t1
+	ins	t2, t1, 16, 3
+	/* SegCtl0 */
+	li      t0, ((MIPS_SEGCFG_MK << MIPS_SEGCFG_AM_SHIFT) |		\
+		(0 << MIPS_SEGCFG_PA_SHIFT) |				\
+		(1 << MIPS_SEGCFG_EU_SHIFT)) |				\
+		(((MIPS_SEGCFG_MK << MIPS_SEGCFG_AM_SHIFT) |		\
+		(0 << MIPS_SEGCFG_PA_SHIFT) |				\
+		(1 << MIPS_SEGCFG_EU_SHIFT)) << 16)
+	or	t0, t2
+	mtc0	t0, $5, 2
+
+	/* SegCtl1 */
+	li      t0, ((MIPS_SEGCFG_MUSUK << MIPS_SEGCFG_AM_SHIFT) |	\
+		(0 << MIPS_SEGCFG_PA_SHIFT) |				\
+		(2 << MIPS_SEGCFG_C_SHIFT) |				\
+		(1 << MIPS_SEGCFG_EU_SHIFT)) |				\
+		(((MIPS_SEGCFG_MUSUK << MIPS_SEGCFG_AM_SHIFT) |		\
+		(0 << MIPS_SEGCFG_PA_SHIFT) |				\
+		(1 << MIPS_SEGCFG_EU_SHIFT)) << 16)
+	ins	t0, t1, 16, 3
+	mtc0	t0, $5, 3
+
+	/* SegCtl2 */
+	li	t0, ((MIPS_SEGCFG_MUSUK << MIPS_SEGCFG_AM_SHIFT) |	\
+		(6 << MIPS_SEGCFG_PA_SHIFT) |				\
+		(1 << MIPS_SEGCFG_EU_SHIFT)) |				\
+		(((MIPS_SEGCFG_MUSUK << MIPS_SEGCFG_AM_SHIFT) |		\
+		(4 << MIPS_SEGCFG_PA_SHIFT) |				\
+		(1 << MIPS_SEGCFG_EU_SHIFT)) << 16)
+	or	t0, t2
+	mtc0	t0, $5, 4
+
+	jal	mips_ihb
+	mfc0    t0, $16, 5
+	li      t2, 0x40000000      /* K bit */
+	or      t0, t0, t2
+	mtc0    t0, $16, 5
+	sync
+	jal	mips_ihb
+
+	.set	pop
+	.endm
+
 	.macro	kernel_entry_setup
-#ifdef CONFIG_MIPS_MT_SMTC
-	mfc0	t0, CP0_CONFIG
-	bgez	t0, 9f
+
+#ifdef CONFIG_EVA
+	sync
+	ehb
+
+	mfc0    t1, CP0_CONFIG
+	bgez    t1, 9f
 	mfc0	t0, CP0_CONFIG, 1
 	bgez	t0, 9f
 	mfc0	t0, CP0_CONFIG, 2
 	bgez	t0, 9f
 	mfc0	t0, CP0_CONFIG, 3
-	and	t0, 1<<2
-	bnez	t0, 0f
+	sll     t0, t0, 6   /* SC bit */
+	bgez    t0, 9f
+
+	platform_eva_init
+	b       0f
 9:
 	/* Assume we came from YAMON... */
 	PTR_LA	v0, 0x9fc00534	/* YAMON print */
 	lw	v0, (v0)
 	move	a0, zero
-	PTR_LA	a1, nonmt_processor
+	PTR_LA  a1, nonsc_processor
 	jal	v0
 
 	PTR_LA	v0, 0x9fc00520	/* YAMON exit */
@@ -34,19 +122,24 @@
 	jal	v0
 
 1:	b	1b
-
+	nop
 	__INITDATA
-nonmt_processor:
-	.asciz	"SMTC kernel requires the MT ASE to run\n"
+nonsc_processor:
+	.asciz  "EVA kernel requires a MIPS core with Segment Control implemented\n"
 	__FINIT
+#endif /* CONFIG_EVA */
 0:
-#endif
 	.endm
 
 /*
  * Do SMP slave processor setup necessary before we can safely execute C code.
  */
 	.macro	smp_slave_setup
+#ifdef CONFIG_EVA
+	sync
+	ehb
+	platform_eva_init
+#endif
 	.endm
 
 #endif /* __ASM_MACH_MIPS_KERNEL_ENTRY_INIT_H */