The code in the initialize_mmu macro sets up MMUv3 memory mapping
identically to MMUv2 fixed memory mapping. Depending on
CONFIG_INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX symbol this code is
-located in one of the following address ranges:
-
- 0xF0000000..0xFFFFFFFF (will keep same address in MMU v2 layout;
- typically ROM)
- 0x00000000..0x07FFFFFF (system RAM; this code is actually linked
- at 0xD0000000..0xD7FFFFFF [cached]
- or 0xD8000000..0xDFFFFFFF [uncached];
- in any case, initially runs elsewhere
- than linked, so have to be careful)
+located in addresses it was linked for (symbol undefined), or not
+(symbol defined), so it needs to be position-independent.
The code has the following assumptions:
This code fragment is run only on an MMU v3.
PA = physical address (two upper nibbles of it);
pc = physical range that contains this code;
-After step 2, we jump to virtual address in 0x40000000..0x5fffffff
-that corresponds to next instruction to execute in this code.
-After step 4, we jump to intended (linked) address of this code.
-
- Step 0 Step1 Step 2 Step3 Step 4 Step5
- ============ ===== ============ ===== ============ =====
- VA PA PA VA PA PA VA PA PA
- ------ -- -- ------ -- -- ------ -- --
- E0..FF -> E0 -> E0 E0..FF -> E0 F0..FF -> F0 -> F0
- C0..DF -> C0 -> C0 C0..DF -> C0 E0..EF -> F0 -> F0
- A0..BF -> A0 -> A0 A0..BF -> A0 D8..DF -> 00 -> 00
- 80..9F -> 80 -> 80 80..9F -> 80 D0..D7 -> 00 -> 00
- 60..7F -> 60 -> 60 60..7F -> 60
- 40..5F -> 40 40..5F -> pc -> pc 40..5F -> pc
- 20..3F -> 20 -> 20 20..3F -> 20
- 00..1F -> 00 -> 00 00..1F -> 00
-
-The default location of IO peripherals is above 0xf0000000. This may change
+After step 2, we jump to virtual address in the range 0x40000000..0x5fffffff
+or 0x00000000..0x1fffffff, depending on whether the kernel was loaded below
+0x40000000 or above. That address corresponds to next instruction to execute
+in this code. After step 4, we jump to intended (linked) address of this code.
+The scheme below assumes that the kernel is loaded below 0x40000000.
+
+ Step0 Step1 Step2 Step3 Step4 Step5
+ ===== ===== ===== ===== ===== =====
+ VA PA PA PA PA VA PA PA
+ ------ -- -- -- -- ------ -- --
+ E0..FF -> E0 -> E0 -> E0 F0..FF -> F0 -> F0
+ C0..DF -> C0 -> C0 -> C0 E0..EF -> F0 -> F0
+ A0..BF -> A0 -> A0 -> A0 D8..DF -> 00 -> 00
+ 80..9F -> 80 -> 80 -> 80 D0..D7 -> 00 -> 00
+ 60..7F -> 60 -> 60 -> 60
+ 40..5F -> 40 -> pc -> pc 40..5F -> pc
+ 20..3F -> 20 -> 20 -> 20
+ 00..1F -> 00 -> 00 -> 00
+
+The default location of IO peripherals is above 0xf0000000. This may be changed
using a "ranges" property in a device tree simple-bus node. See ePAPR 1.1, ยง6.5
for details on the syntax and semantic of simple-bus nodes. The following
limitations apply:
If unsure, leave the default value here.
+config KERNEL_LOAD_ADDRESS
+ hex "Kernel load address"
+ default 0x00003000
+ help
+ This is the address where the kernel is loaded.
+ It is virtual address for MMUv2 configurations and physical address
+ for all other configurations.
+
+ If unsure, leave the default value here.
+
+config VECTORS_OFFSET
+ hex "Kernel vectors offset"
+ default 0x00003000
+ help
+ This is the offset of the kernel image from the relocatable vectors
+ base.
+
+ If unsure, leave the default value here.
+
choice
prompt "KSEG layout"
depends on MMU
used when no physical memory size is passed through DTB or through
boot parameter from bootloader.
- In noMMU configuration the following parameters are derived from it:
- - kernel load address;
- - kernel entry point address;
- - relocatable vectors base address;
- - uBoot load address;
- - TASK_SIZE.
+ It's also used for TASK_SIZE calculation in noMMU configuration.
If unsure, leave the default value here.
*(.ResetVector.text)
}
- .image KERNELOFFSET: AT (LOAD_MEMORY_ADDRESS)
+ .image KERNELOFFSET: AT (CONFIG_KERNEL_LOAD_ADDRESS)
{
_image_start = .;
*(image)
.align 4
RomInitAddr:
- .word LOAD_MEMORY_ADDRESS
+#if defined(CONFIG_INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX) && \
+ XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY
+ .word CONFIG_KERNEL_LOAD_ADDRESS
+#else
+ .word KERNELOFFSET
+#endif
RomBootParam:
.word _bootparam
_bootparam:
# for more details.
#
-ifdef CONFIG_MMU
-ifdef CONFIG_INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
-UIMAGE_LOADADDR = 0x00003000
-else
-UIMAGE_LOADADDR = 0xd0003000
-endif
-else
-UIMAGE_LOADADDR = $(shell printf "0x%x" $$(( ${CONFIG_DEFAULT_MEM_START} + 0x3000 )) )
-endif
+UIMAGE_LOADADDR = $(CONFIG_KERNEL_LOAD_ADDRESS)
UIMAGE_COMPRESSION = gzip
$(obj)/../uImage: vmlinux.bin.gz FORCE
.align 4
1: movi a2, 0x10000000
- movi a3, 0x18000000
- add a2, a2, a0
-9: bgeu a2, a3, 9b /* PC is out of the expected range */
+
+#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, 0x40000000 | XCHAL_SPANNING_WAY
+ movi a2, TEMP_MAPPING_VADDR | XCHAL_SPANNING_WAY
idtlb a2
iitlb a2
isync
srli a3, a0, 27
slli a3, a3, 27
addi a3, a3, CA_BYPASS
- addi a7, a2, -1
+ 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, -6
+ addi a5, a2, -XCHAL_SPANNING_WAY
add a4, a4, a5
jx a4
witlb a4, a5
#endif
- movi a5, XCHAL_KIO_CACHED_VADDR + 6
+ 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 + 6
+ 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 MMU v2 mappings. */
+ /* Jump to self, using final mappings. */
movi a4, 1f
jx a4
#define XCHAL_KSEG_SIZE __XTENSA_UL_CONST(0x08000000)
#define XCHAL_KSEG_ALIGNMENT __XTENSA_UL_CONST(0x08000000)
#define XCHAL_KSEG_TLB_WAY 5
+#define XCHAL_KIO_TLB_WAY 6
#elif defined(CONFIG_XTENSA_KSEG_256M)
#define XCHAL_KSEG_SIZE __XTENSA_UL_CONST(0x10000000)
#define XCHAL_KSEG_ALIGNMENT __XTENSA_UL_CONST(0x10000000)
#define XCHAL_KSEG_TLB_WAY 6
+#define XCHAL_KIO_TLB_WAY 6
#elif defined(CONFIG_XTENSA_KSEG_512M)
#define XCHAL_KSEG_SIZE __XTENSA_UL_CONST(0x20000000)
#define XCHAL_KSEG_ALIGNMENT __XTENSA_UL_CONST(0x10000000)
#define XCHAL_KSEG_TLB_WAY 6
+#define XCHAL_KIO_TLB_WAY 6
#else
#error Unsupported KSEG configuration
#ifdef CONFIG_MMU
#define PAGE_OFFSET XCHAL_KSEG_CACHED_VADDR
+#define PHYS_OFFSET XCHAL_KSEG_PADDR
#define MAX_LOW_PFN (PHYS_PFN(XCHAL_KSEG_PADDR) + \
PHYS_PFN(XCHAL_KSEG_SIZE))
#else
#define PAGE_OFFSET __XTENSA_UL_CONST(0)
+#define PHYS_OFFSET __XTENSA_UL_CONST(0)
#define MAX_LOW_PFN (PHYS_PFN(PLATFORM_DEFAULT_MEM_START) + \
PHYS_PFN(PLATFORM_DEFAULT_MEM_SIZE))
#endif
#define ARCH_PFN_OFFSET (PLATFORM_DEFAULT_MEM_START >> PAGE_SHIFT)
-#define __pa(x) ((unsigned long) (x) - PAGE_OFFSET)
-#define __va(x) ((void *)((unsigned long) (x) + PAGE_OFFSET))
+#define __pa(x) \
+ ((unsigned long) (x) - PAGE_OFFSET + PHYS_OFFSET)
+#define __va(x) \
+ ((void *)((unsigned long) (x) - PHYS_OFFSET + PAGE_OFFSET))
#define pfn_valid(pfn) \
((pfn) >= ARCH_PFN_OFFSET && ((pfn) - ARCH_PFN_OFFSET) < max_mapnr)
#if defined(CONFIG_MMU)
-/* Will Become VECBASE */
-#define VIRTUAL_MEMORY_ADDRESS XCHAL_KSEG_CACHED_VADDR
-
+#if XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY
/* Image Virtual Start Address */
-#define KERNELOFFSET (XCHAL_KSEG_CACHED_VADDR + 0x3000)
-
-#if defined(XCHAL_HAVE_PTP_MMU) && XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY
- /* MMU v3 - XCHAL_HAVE_PTP_MMU == 1 */
- #define LOAD_MEMORY_ADDRESS 0x00003000
+#define KERNELOFFSET (XCHAL_KSEG_CACHED_VADDR + \
+ CONFIG_KERNEL_LOAD_ADDRESS - \
+ XCHAL_KSEG_PADDR)
#else
- /* MMU V2 - XCHAL_HAVE_PTP_MMU == 0 */
- #define LOAD_MEMORY_ADDRESS 0xD0003000
+#define KERNELOFFSET CONFIG_KERNEL_LOAD_ADDRESS
#endif
-#define RESET_VECTOR1_VADDR (VIRTUAL_MEMORY_ADDRESS + \
- XCHAL_RESET_VECTOR1_PADDR)
-
#else /* !defined(CONFIG_MMU) */
/* MMU Not being used - Virtual == Physical */
- /* VECBASE */
- #define VIRTUAL_MEMORY_ADDRESS (PLATFORM_DEFAULT_MEM_START + 0x2000)
+/* Location of the start of the kernel text, _start */
+#define KERNELOFFSET CONFIG_KERNEL_LOAD_ADDRESS
- /* Location of the start of the kernel text, _start */
- #define KERNELOFFSET (PLATFORM_DEFAULT_MEM_START + 0x3000)
-
- /* Loaded just above possibly live vectors */
- #define LOAD_MEMORY_ADDRESS (PLATFORM_DEFAULT_MEM_START + 0x3000)
-
-#define RESET_VECTOR1_VADDR (XCHAL_RESET_VECTOR1_VADDR)
#endif /* CONFIG_MMU */
-#define XC_VADDR(offset) (VIRTUAL_MEMORY_ADDRESS + offset)
-
-/* Used to set VECBASE register */
-#define VECBASE_RESET_VADDR VIRTUAL_MEMORY_ADDRESS
+#define RESET_VECTOR1_VADDR (XCHAL_RESET_VECTOR1_VADDR)
+#define VECBASE_VADDR (KERNELOFFSET - CONFIG_VECTORS_OFFSET)
#if defined(XCHAL_HAVE_VECBASE) && XCHAL_HAVE_VECBASE
-#define USER_VECTOR_VADDR XC_VADDR(XCHAL_USER_VECOFS)
-#define KERNEL_VECTOR_VADDR XC_VADDR(XCHAL_KERNEL_VECOFS)
-#define DOUBLEEXC_VECTOR_VADDR XC_VADDR(XCHAL_DOUBLEEXC_VECOFS)
-#define WINDOW_VECTORS_VADDR XC_VADDR(XCHAL_WINDOW_OF4_VECOFS)
-#define INTLEVEL2_VECTOR_VADDR XC_VADDR(XCHAL_INTLEVEL2_VECOFS)
-#define INTLEVEL3_VECTOR_VADDR XC_VADDR(XCHAL_INTLEVEL3_VECOFS)
-#define INTLEVEL4_VECTOR_VADDR XC_VADDR(XCHAL_INTLEVEL4_VECOFS)
-#define INTLEVEL5_VECTOR_VADDR XC_VADDR(XCHAL_INTLEVEL5_VECOFS)
-#define INTLEVEL6_VECTOR_VADDR XC_VADDR(XCHAL_INTLEVEL6_VECOFS)
-
-#define DEBUG_VECTOR_VADDR XC_VADDR(XCHAL_DEBUG_VECOFS)
+#define VECTOR_VADDR(offset) (VECBASE_VADDR + offset)
-#define NMI_VECTOR_VADDR XC_VADDR(XCHAL_NMI_VECOFS)
-
-#define INTLEVEL7_VECTOR_VADDR XC_VADDR(XCHAL_INTLEVEL7_VECOFS)
+#define USER_VECTOR_VADDR VECTOR_VADDR(XCHAL_USER_VECOFS)
+#define KERNEL_VECTOR_VADDR VECTOR_VADDR(XCHAL_KERNEL_VECOFS)
+#define DOUBLEEXC_VECTOR_VADDR VECTOR_VADDR(XCHAL_DOUBLEEXC_VECOFS)
+#define WINDOW_VECTORS_VADDR VECTOR_VADDR(XCHAL_WINDOW_OF4_VECOFS)
+#define INTLEVEL2_VECTOR_VADDR VECTOR_VADDR(XCHAL_INTLEVEL2_VECOFS)
+#define INTLEVEL3_VECTOR_VADDR VECTOR_VADDR(XCHAL_INTLEVEL3_VECOFS)
+#define INTLEVEL4_VECTOR_VADDR VECTOR_VADDR(XCHAL_INTLEVEL4_VECOFS)
+#define INTLEVEL5_VECTOR_VADDR VECTOR_VADDR(XCHAL_INTLEVEL5_VECOFS)
+#define INTLEVEL6_VECTOR_VADDR VECTOR_VADDR(XCHAL_INTLEVEL6_VECOFS)
+#define INTLEVEL7_VECTOR_VADDR VECTOR_VADDR(XCHAL_INTLEVEL7_VECOFS)
+#define DEBUG_VECTOR_VADDR VECTOR_VADDR(XCHAL_DEBUG_VECOFS)
/*
* These XCHAL_* #defines from varian/core.h
* constants are defined above and should be used.
*/
#undef XCHAL_VECBASE_RESET_VADDR
-#undef XCHAL_RESET_VECTOR0_VADDR
#undef XCHAL_USER_VECTOR_VADDR
#undef XCHAL_KERNEL_VECTOR_VADDR
#undef XCHAL_DOUBLEEXC_VECTOR_VADDR
#undef XCHAL_INTLEVEL4_VECTOR_VADDR
#undef XCHAL_INTLEVEL5_VECTOR_VADDR
#undef XCHAL_INTLEVEL6_VECTOR_VADDR
-#undef XCHAL_DEBUG_VECTOR_VADDR
-#undef XCHAL_NMI_VECTOR_VADDR
#undef XCHAL_INTLEVEL7_VECTOR_VADDR
+#undef XCHAL_DEBUG_VECTOR_VADDR
#else
#define INTLEVEL4_VECTOR_VADDR XCHAL_INTLEVEL4_VECTOR_VADDR
#define INTLEVEL5_VECTOR_VADDR XCHAL_INTLEVEL5_VECTOR_VADDR
#define INTLEVEL6_VECTOR_VADDR XCHAL_INTLEVEL6_VECTOR_VADDR
+#define INTLEVEL7_VECTOR_VADDR XCHAL_INTLEVEL6_VECTOR_VADDR
#define DEBUG_VECTOR_VADDR XCHAL_DEBUG_VECTOR_VADDR
#endif
* The messy computation for 'pteval' above really simplifies
* into the following:
*
- * pteval = ((pmdval - PAGE_OFFSET) & PAGE_MASK) | PAGE_DIRECTORY
+ * pteval = ((pmdval - PAGE_OFFSET + PHYS_OFFSET) & PAGE_MASK)
+ * | PAGE_DIRECTORY
*/
- movi a1, (-PAGE_OFFSET) & 0xffffffff
+ movi a1, (PHYS_OFFSET - PAGE_OFFSET) & 0xffffffff
add a0, a0, a1 # pmdval - PAGE_OFFSET
extui a1, a0, 0, PAGE_SHIFT # ... & PAGE_MASK
xor a0, a0, a1
movi a0, 0
#if XCHAL_HAVE_VECBASE
- movi a2, VECBASE_RESET_VADDR
+ movi a2, VECBASE_VADDR
wsr a2, vecbase
#endif
jiffies = jiffies_64;
#endif
-#ifndef KERNELOFFSET
-#define KERNELOFFSET 0xd0003000
-#endif
-
/* Note: In the following macros, it would be nice to specify only the
vector name and section kind and construct "sym" and "section" using
CPP concatenation, but that does not work reliably. Concatenating a
projects / cascardo / linux.git / commitdiff