linux/arch/arc/include/asm
Vineet Gupta 26f9d5fd82 ARC: support HIGHMEM even without PAE40
Initial HIGHMEM support on ARC was introduced for PAE40 where the low
memory (0x8000_0000 based) and high memory (0x1_0000_0000) were
physically contiguous. So CONFIG_FLATMEM sufficed (despite a peipheral
hole in the middle, which wasted a bit of struct page memory, but things
worked).

However w/o PAE, highmem was not possible and we could only reach
~1.75GB of DDR. Now there is a use case to access ~4GB of DDR w/o PAE40
The idea is to have low memory at canonical 0x8000_0000 and highmem
at 0 so enire 4GB address space is available for physical addressing
This needs additional platform/interconnect mapping to convert
the non contiguous physical addresses into linear bus adresses.

From Linux point of view, non contiguous divide means FLATMEM no
longer works and DISCONTIGMEM is needed to track the pfns in the 2
regions.

This scheme would also work for PAE40, only better in that we don't
waste struct page memory for the peripheral hole.

The DT description will be something like

    memory {
        ...
        reg = <0x80000000 0x200000000   /* 512MB: lowmem */
               0x00000000 0x10000000>;  /* 256MB: highmem */
   }

Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-05 16:35:46 +05:30
..
arcregs.h ARC: build: Better way to detect ISA compatible toolchain 2016-03-12 11:58:30 +05:30
asm-offsets.h
atomic.h atomic, arch: Audit atomic_{read,set}() 2015-09-23 09:54:28 +02:00
barrier.h ARCv2: barriers 2015-06-25 06:00:17 +05:30
bitops.h ARC: bitops: Remove non relevant comments 2016-03-11 14:59:54 +05:30
bug.h ARC: BUG() dumps stack after @msg (@msg now same as in generic BUG)) 2014-10-13 14:46:18 +05:30
cache.h ARCv2: ioremap: Support dynamic peripheral address space 2016-03-19 14:34:10 +05:30
cacheflush.h ARC: dma: ioremap: use phys_addr_t consistenctly in code paths 2016-03-19 14:34:09 +05:30
checksum.h ipv4: Update parameters for csum_tcpudp_magic to their original types 2016-03-13 23:55:13 -04:00
clk.h
cmpxchg.h ARC: Fix misspellings in comments. 2016-03-11 14:59:53 +05:30
current.h ARC: remove extraneous __KERNEL__ guards 2014-10-13 14:46:20 +05:30
delay.h ARCv2: Adhere to Zero Delay loop restriction 2015-06-22 14:06:56 +05:30
disasm.h ARC: disassembly (needed by kprobes/kgdb/unaligned-access-emul) 2013-02-15 23:16:04 +05:30
dma-mapping.h ARC: dma: reintroduce platform specific dma<->phys 2016-03-19 14:34:09 +05:30
dma.h ARC: Add PCI support 2016-03-10 14:44:13 -06:00
elf.h ARCv2: Support for ARCv2 ISA and HS38x cores 2015-06-22 14:06:55 +05:30
entry-arcv2.h ARCv2: Support for ARCv2 ISA and HS38x cores 2015-06-22 14:06:55 +05:30
entry-compact.h ARC: Fix misspellings in comments. 2016-03-11 14:59:53 +05:30
entry.h ARCv2: STAR 9000808988: signals involving Delay Slot 2015-06-22 14:06:55 +05:30
exec.h
fb.h arc: Add our own implementation of fb_pgprotect() 2016-04-07 14:59:09 +05:30
futex.h ARC: change some branchs to jumps to resolve linkage errors 2015-08-20 18:53:15 +05:30
highmem.h ARC: mm: HIGHMEM: kmap API implementation 2015-10-28 19:49:04 +05:30
hugepage.h ARC, thp: remove infrastructure for handling splitting PMDs 2016-03-17 15:09:34 -07:00
io.h ARC: Add missing io barriers to io{read,write}{16,32}be() 2016-05-05 16:35:28 +05:30
irq.h ARCv2: SMP: Push IPI_IRQ into IPI provider 2016-02-24 11:07:31 +05:30
irqflags-arcv2.h ARCv2: Enable LOCKDEP 2016-04-22 18:12:31 +05:30
irqflags-compact.h ARC: Abstract out ISA specific SLEEP args 2015-11-16 14:17:02 +05:30
irqflags.h ARCv2: Support for ARCv2 ISA and HS38x cores 2015-06-22 14:06:55 +05:30
Kbuild Merge branch 'strscpy' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile 2015-10-04 16:31:13 +01:00
kdebug.h
kgdb.h ARC: Update order of registers in KGDB to match GDB 7.5 2014-10-13 14:46:20 +05:30
kmap_types.h ARC: mm: HIGHMEM: kmap API implementation 2015-10-28 19:49:04 +05:30
kprobes.h ARC: Remove explicit passing around of ECR 2013-06-26 15:30:50 +05:30
linkage.h ARC: switch to generic ENTRY/END assembler annotations 2014-03-26 14:31:28 +05:30
mach_desc.h ARC: smp: Rename platform hook @init_cpu_smp -> @init_per_cpu 2015-12-17 12:56:56 +05:30
mcip.h ARCv2: clocksource: Rename GRTC -> GFRC ... 2016-01-29 16:51:02 +05:30
mmu_context.h ARC: [SMP] TLB flush 2013-11-06 10:41:45 +05:30
mmu.h ARC: mm: PAE40 support 2015-10-29 18:41:30 +05:30
mmzone.h ARC: support HIGHMEM even without PAE40 2016-05-05 16:35:46 +05:30
module.h
mutex.h
page.h ARC: support HIGHMEM even without PAE40 2016-05-05 16:35:46 +05:30
pci.h ARC: Add PCI support 2016-03-10 14:44:13 -06:00
perf_event.h ARCv2: perf: Finally introduce HS perf unit 2015-08-27 14:59:07 +05:30
pgalloc.h ARC: mm: PAE40 support 2015-10-29 18:41:30 +05:30
pgtable.h ARC: Fix PAE40 boot failures due to PTE truncation 2016-05-05 16:35:45 +05:30
processor.h ARC: cpu_relax() to be compiler barrier even for UP 2015-11-14 13:12:30 +05:30
ptrace.h ARC: Make pt_regs regs unsigned 2015-08-05 11:48:21 +05:30
sections.h of/fdt: consolidate built-in dtb section variables 2014-04-30 00:59:13 -05:00
segment.h
serial.h ARC: Dynamically determine BASE_BAUD from DeviceTree 2015-02-02 17:08:37 +05:30
setup.h ARC: boot log: move helper macros to header for reuse 2015-10-17 17:48:25 +05:30
shmparam.h ARC: [mm] Aliasing VIPT dcache support 4/4 2013-05-09 22:00:57 +05:30
smp.h ARC: rename smp operation init_irq_cpu() to init_per_cpu() 2015-12-17 12:56:43 +05:30
spinlock_types.h ARC: LLOCK/SCOND based rwlock 2015-08-04 09:26:33 +05:30
spinlock.h ARCv2: spinlock/rwlock/atomics: reduce 1 instruction in exponential backoff 2015-08-07 13:56:16 +05:30
stacktrace.h ARC: Make arc_unwind_core accessible externally 2015-02-27 10:15:00 +05:30
string.h ARC: remove extraneous __KERNEL__ guards 2014-10-13 14:46:20 +05:30
switch_to.h
syscall.h ARC: stop using pt_regs->orig_r8 2013-06-22 19:23:26 +05:30
syscalls.h ARC: remove extraneous __KERNEL__ guards 2014-10-13 14:46:20 +05:30
thread_info.h ARCv2: Support for ARCv2 ISA and HS38x cores 2015-06-22 14:06:55 +05:30
timex.h
tlb-mmu1.h ARC: Disintegrate arcregs.h 2013-06-22 13:46:42 +05:30
tlb.h ARC: Disintegrate arcregs.h 2013-06-22 13:46:42 +05:30
tlbflush.h ARC: thp: unbork !CONFIG_TRANSPARENT_HUGEPAGE build 2016-03-17 15:31:45 +05:30
uaccess.h ARCv2: Adhere to Zero Delay loop restriction 2015-06-22 14:06:56 +05:30
unaligned.h ARC: rename kconfig option for unaligned emulation 2014-10-13 14:46:15 +05:30
unwind.h ARC: dw2 unwind: Reinstante unwinding out of modules 2015-12-17 11:10:23 +05:30