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-rw-r--r--arch/xtensa/include/asm/initialize_mmu.h245
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diff --git a/arch/xtensa/include/asm/initialize_mmu.h b/arch/xtensa/include/asm/initialize_mmu.h
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+++ b/arch/xtensa/include/asm/initialize_mmu.h
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+/*
+ * arch/xtensa/include/asm/initialize_mmu.h
+ *
+ * Initializes MMU:
+ *
+ * For the new V3 MMU we remap the TLB from virtual == physical
+ * to the standard Linux mapping used in earlier MMU's.
+ *
+ * For the MMU we also support a new configuration register that
+ * specifies how the S32C1I instruction operates with the cache
+ * controller.
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of
+ * this archive for more details.
+ *
+ * Copyright (C) 2008 - 2012 Tensilica, Inc.
+ *
+ * Marc Gauthier <marc@tensilica.com>
+ * Pete Delaney <piet@tensilica.com>
+ */
+
+#ifndef _XTENSA_INITIALIZE_MMU_H
+#define _XTENSA_INITIALIZE_MMU_H
+
+#include <linux/init.h>
+#include <linux/pgtable.h>
+#include <asm/vectors.h>
+
+#if XCHAL_HAVE_PTP_MMU
+#define CA_BYPASS (_PAGE_CA_BYPASS | _PAGE_HW_WRITE | _PAGE_HW_EXEC)
+#define CA_WRITEBACK (_PAGE_CA_WB | _PAGE_HW_WRITE | _PAGE_HW_EXEC)
+#else
+#define CA_WRITEBACK (0x4)
+#endif
+
+#ifdef __ASSEMBLY__
+
+#define XTENSA_HWVERSION_RC_2009_0 230000
+
+ .macro initialize_mmu
+
+#if XCHAL_HAVE_S32C1I && (XCHAL_HW_MIN_VERSION >= XTENSA_HWVERSION_RC_2009_0)
+/*
+ * We Have Atomic Operation Control (ATOMCTL) Register; Initialize it.
+ * For details see Documentation/xtensa/atomctl.rst
+ */
+#if XCHAL_DCACHE_IS_COHERENT
+ movi a3, 0x25 /* For SMP/MX -- internal for writeback,
+ * RCW otherwise
+ */
+#else
+ movi a3, 0x29 /* non-MX -- Most cores use Std Memory
+ * Controlers which usually can't use RCW
+ */
+#endif
+ wsr a3, atomctl
+#endif /* XCHAL_HAVE_S32C1I &&
+ * (XCHAL_HW_MIN_VERSION >= XTENSA_HWVERSION_RC_2009_0)
+ */
+
+#if defined(CONFIG_MMU) && XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY
+/*
+ * Have MMU v3
+ */
+
+#if !XCHAL_HAVE_VECBASE
+# error "MMU v3 requires reloc vectors"
+#endif
+
+ movi a1, 0
+ _call0 1f
+ _j 2f
+
+ .align 4
+1:
+
+#if CONFIG_KERNEL_LOAD_ADDRESS < 0x40000000ul
+#define TEMP_MAPPING_VADDR 0x40000000
+#else
+#define TEMP_MAPPING_VADDR 0x00000000
+#endif
+
+ /* Step 1: invalidate mapping at 0x40000000..0x5FFFFFFF. */
+
+ movi a2, TEMP_MAPPING_VADDR | XCHAL_SPANNING_WAY
+ idtlb a2
+ iitlb a2
+ isync
+
+ /* Step 2: map 0x40000000..0x47FFFFFF to paddr containing this code
+ * and jump to the new mapping.
+ */
+
+ srli a3, a0, 27
+ slli a3, a3, 27
+ addi a3, a3, CA_BYPASS
+ addi a7, a2, 5 - XCHAL_SPANNING_WAY
+ wdtlb a3, a7
+ witlb a3, a7
+ isync
+
+ slli a4, a0, 5
+ srli a4, a4, 5
+ addi a5, a2, -XCHAL_SPANNING_WAY
+ add a4, a4, a5
+ jx a4
+
+ /* Step 3: unmap everything other than current area.
+ * Start at 0x60000000, wrap around, and end with 0x20000000
+ */
+2: movi a4, 0x20000000
+ add a5, a2, a4
+3: idtlb a5
+ iitlb a5
+ add a5, a5, a4
+ bne a5, a2, 3b
+
+ /* Step 4: Setup MMU with the requested static mappings. */
+
+ movi a6, 0x01000000
+ wsr a6, ITLBCFG
+ wsr a6, DTLBCFG
+ isync
+
+ movi a5, XCHAL_KSEG_CACHED_VADDR + XCHAL_KSEG_TLB_WAY
+ movi a4, XCHAL_KSEG_PADDR + CA_WRITEBACK
+ wdtlb a4, a5
+ witlb a4, a5
+
+ movi a5, XCHAL_KSEG_BYPASS_VADDR + XCHAL_KSEG_TLB_WAY
+ movi a4, XCHAL_KSEG_PADDR + CA_BYPASS
+ wdtlb a4, a5
+ witlb a4, a5
+
+#ifdef CONFIG_XTENSA_KSEG_512M
+ movi a5, XCHAL_KSEG_CACHED_VADDR + 0x10000000 + XCHAL_KSEG_TLB_WAY
+ movi a4, XCHAL_KSEG_PADDR + 0x10000000 + CA_WRITEBACK
+ wdtlb a4, a5
+ witlb a4, a5
+
+ movi a5, XCHAL_KSEG_BYPASS_VADDR + 0x10000000 + XCHAL_KSEG_TLB_WAY
+ movi a4, XCHAL_KSEG_PADDR + 0x10000000 + CA_BYPASS
+ wdtlb a4, a5
+ witlb a4, a5
+#endif
+
+ movi a5, XCHAL_KIO_CACHED_VADDR + XCHAL_KIO_TLB_WAY
+ movi a4, XCHAL_KIO_DEFAULT_PADDR + CA_WRITEBACK
+ wdtlb a4, a5
+ witlb a4, a5
+
+ movi a5, XCHAL_KIO_BYPASS_VADDR + XCHAL_KIO_TLB_WAY
+ movi a4, XCHAL_KIO_DEFAULT_PADDR + CA_BYPASS
+ wdtlb a4, a5
+ witlb a4, a5
+
+ isync
+
+ /* Jump to self, using final mappings. */
+ movi a4, 1f
+ jx a4
+
+1:
+ /* Step 5: remove temporary mapping. */
+ idtlb a7
+ iitlb a7
+ isync
+
+ movi a0, 0
+ wsr a0, ptevaddr
+ rsync
+
+#endif /* defined(CONFIG_MMU) && XCHAL_HAVE_PTP_MMU &&
+ XCHAL_HAVE_SPANNING_WAY */
+
+ .endm
+
+ .macro initialize_cacheattr
+
+#if !defined(CONFIG_MMU) && (XCHAL_HAVE_TLBS || XCHAL_HAVE_MPU)
+#if CONFIG_MEMMAP_CACHEATTR == 0x22222222 && XCHAL_HAVE_PTP_MMU
+#error Default MEMMAP_CACHEATTR of 0x22222222 does not work with full MMU.
+#endif
+
+#if XCHAL_HAVE_MPU
+ __REFCONST
+ .align 4
+.Lattribute_table:
+ .long 0x000000, 0x1fff00, 0x1ddf00, 0x1eef00
+ .long 0x006600, 0x000000, 0x000000, 0x000000
+ .long 0x000000, 0x000000, 0x000000, 0x000000
+ .long 0x000000, 0x000000, 0x000000, 0x000000
+ .previous
+
+ movi a3, .Lattribute_table
+ movi a4, CONFIG_MEMMAP_CACHEATTR
+ movi a5, 1
+ movi a6, XCHAL_MPU_ENTRIES
+ movi a10, 0x20000000
+ movi a11, -1
+1:
+ sub a5, a5, a10
+ extui a8, a4, 28, 4
+ beq a8, a11, 2f
+ addi a6, a6, -1
+ mov a11, a8
+2:
+ addx4 a9, a8, a3
+ l32i a9, a9, 0
+ or a9, a9, a6
+ wptlb a9, a5
+ slli a4, a4, 4
+ bgeu a5, a10, 1b
+
+#else
+ movi a5, XCHAL_SPANNING_WAY
+ movi a6, ~_PAGE_ATTRIB_MASK
+ movi a4, CONFIG_MEMMAP_CACHEATTR
+ movi a8, 0x20000000
+1:
+ rdtlb1 a3, a5
+ xor a3, a3, a4
+ and a3, a3, a6
+ xor a3, a3, a4
+ wdtlb a3, a5
+ ritlb1 a3, a5
+ xor a3, a3, a4
+ and a3, a3, a6
+ xor a3, a3, a4
+ witlb a3, a5
+
+ add a5, a5, a8
+ srli a4, a4, 4
+ bgeu a5, a8, 1b
+
+ isync
+#endif
+#endif
+
+ .endm
+
+#endif /*__ASSEMBLY__*/
+
+#endif /* _XTENSA_INITIALIZE_MMU_H */