The Malta board aliases 0x80000000 - 0xffffffff to 0x00000000
- 0x7fffffff ignoring the 256 MB IO hole in 0x10000000.
The physical memory is shifted to 0x80000000 so up to 2GB
can be used. Kuseg is expanded to 3GB (due to board limitations
only 2GB can be accessed) and lowmem (kernel space) is expanded to 2GB.
The Segment Control registers are programmed as follows:
Virtual memory Physical memory Mapping
0x00000000 - 0x7fffffff 0x80000000 - 0xfffffffff MUSUK (kuseg)
0x80000000 - 0x9fffffff 0x00000000 - 0x1ffffffff MUSUK (kseg0)
0xa0000000 - 0xbf000000 0x00000000 - 0x1ffffffff MUSUK (kseg1)
0xc0000000 - 0xdfffffff - MK (kseg2)
0xe0000000 - 0xffffffff - MK (kseg3)
The location of exception vectors remain the same since 0xbfc00000
(traditional exception base) still maps to 0x1fc00000 physical.
Signed-off-by: Markos Chandras <markos.chandras@xxxxxxxxxx>
---
.../include/asm/mach-malta/kernel-entry-init.h | 109 ++++++++++++++++++++-
arch/mips/mti-malta/malta-setup.c | 4 +
2 files changed, 112 insertions(+), 1 deletion(-)
diff --git a/arch/mips/include/asm/mach-malta/kernel-entry-init.h b/arch/mips/include/asm/mach-malta/kernel-entry-init.h
index 0b793e7..9bace9c 100644
--- a/arch/mips/include/asm/mach-malta/kernel-entry-init.h
+++ b/arch/mips/include/asm/mach-malta/kernel-entry-init.h
@@ -5,10 +5,80 @@
*
* Chris Dearman (chris@xxxxxxxx)
* 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
+ /*
+ * Prepare segments for EVA boot:
+ *
+ * This is in case the processor boots in legacy configuration
+ * (SI_EVAReset is de-asserted and CONFIG5.K == 0)
+ *
+ * On entry, t1 is loaded with CP0_CONFIG
+ *
+ * ========================= 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
+ */
+ .macro eva_entry
+ /*
+ * Get Config.K0 value and use it to program
+ * the segmentation registers
+ */
+ 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
+ .endm
+
.macro kernel_entry_setup
#ifdef CONFIG_MIPS_MT_SMTC
mfc0 t0, CP0_CONFIG
@@ -39,8 +109,45 @@
nonmt_processor:
.asciz "SMTC kernel requires the MT ASE to run\n"
__FINIT
-0:
#endif
+
+#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
+ sll t0, t0, 6 /* SC bit */
+ bgez t0, 9f
+
+ eva_entry
+ b 0f
+9:
+ /* Assume we came from YAMON... */
+ PTR_LA v0, 0x9fc00534 /* YAMON print */
+ lw v0, (v0)
+ move a0, zero
+ PTR_LA a1, nonsc_processor
+ jal v0
+
+ PTR_LA v0, 0x9fc00520 /* YAMON exit */
+ lw v0, (v0)
+ li a0, 1
+ jal v0
+
+1: b 1b
+ nop
+ __INITDATA
+nonsc_processor:
+ .asciz "EVA kernel requires a MIPS core with Segment Control implemented\n"
+ __FINIT
+#endif /* CONFIG_EVA */
+0:
.endm
/*
diff --git a/arch/mips/mti-malta/malta-setup.c b/arch/mips/mti-malta/malta-setup.c
index c72a069..35057a8 100644
--- a/arch/mips/mti-malta/malta-setup.c
+++ b/arch/mips/mti-malta/malta-setup.c
@@ -247,6 +247,10 @@ void __init plat_mem_setup(void)
{
unsigned int i;
+ if (config_enabled(CONFIG_EVA))
+ /* EVA has already been configured in mach-malta/kernel-init.h */
+ pr_info("Enhanced Virtual Addressing (EVA) activated\n");
+
mips_pcibios_init();
/* Request I/O space for devices used on the Malta board. */
--
1.8.5.3
