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−Table of Contents
Linux port for Xtensa
- Linux git tree: https://github.com/jcmvbkbc/linux-xtensa
- Build/test tools git tree: https://github.com/jcmvbkbc/xtensa-linux-test
- Toolchain build scripts/overlays git tree: https://github.com/jcmvbkbc/xtensa-toolchain-build
TODO
- coprocessors support in SMP
- dynamic ftrace
- kprobes
- kgdb/kdb
- kexec
- NX
In Progress
Done
eXecute In Place
XIP done, in the mainline:
7af710d98877 xtensa: add XIP kernel support
QEMU virt machine
Done, in the mainline:
775f1f7eaced xtensa: virt: add defconfig and DTS
support for cores with MPU
Done, in the mainline:
a5944195d00a xtensa: implement initialize_cacheattr for MPU cores
exclusive access support (l32ex/s32ex)
Done, in the mainline:
f7c34874f04a xtensa: add exclusive atomics support
ticket spinlocks
Done, in the mainline:
af3d890b4303 xtensa: provide xchg for sizes 1 and 2 579afe866f52 xtensa: use generic spinlock/rwlock implementation
support xtfpga audio hardware in ALSA
Done, in the mainline:
57b7068de5d0 ASoC: add xtensa xtfpga I2S interface and platform 0c7665c35602 clk: TI CDCE706 clock synthesizer driver 3a33a85401ec i2c: ocores: fix clock-frequency binding usage e961a094afe0 i2c: ocores: add common clock support c2c62e61fb85 xtensa: xtfpga: add audio card to xtfpga DTS 04ddc5b5ad4e xtensa: xtfpga: provide defconfig with audio subsystem
fixes for debuggability (continuous stack trace over exceptions at least)
Done, in the mainline:
b6569439f1ce xtensa: keep exception/interrupt stack continuous
NoMMU fixes
Done, in the xtensa-fixes branch:
f04f3cb xtensa: nommu: move init_mmu stub to nommu_context.h 67dbc24 xtensa: nommu: provide __invalidate_dcache_page_alias stub ae73a13 xtensa: nommu: provide _PAGE_CHG_MASK definition 1103273 xtensa: nommu: provide MAP_UNINITIALIZED definition de03359 xtensa: nommu: don't provide arch_get_unmapped_area 4ee9b59 xtensa: nommu: don't build most of the cache flushing code 8cd28c7 xtensa: nommu: add MMU dependency to DEBUG_TLB_SANITY 93c3d27 xtensa: nommu: fix Image.elf reset code and ld script 1b929c7 xtensa: nommu: fix load address definitions 7c5b218 xtensa: nommu: fix uImage load address e40e0ee xtensa: move vecbase SR initialization to _startup f698bc8 xtensa: nommu: set up cache and atomctl in initialize_mmu 48243b5 xtensa: nommu: reserve memory below PLATFORM_DEFAULT_MEM_START ceef25a xtensa: nommu: clean up memory map dump 8fd689e xtensa: make PLATFORM_DEFAULT_MEM parameters configurable
Deliver signals raised in double exceptions
Not really needed. Replaced with alignment double exception fixup, special handler for user stack alignment and deprecation of fast atomic and spill syscalls. In the mainline (v3.17-rc3):
c3ef1f4 xtensa: add double exception fixup handler for fast_unaligned e9500dd xtensa: make fast_unaligned store restartable 3cfc096 xtensa: don't allow overflow/underflow on unaligned stack 9184289 xtensa: deprecate fast_xtensa and fast_spill_registers syscalls
Highmem on cores with aliasing cache
Done, in the mainline (v3.17-rc3):
22def76 xtensa: make fixmap region addressing grow with index dec7305 xtensa: allow fixmap and kmap span more than one page table 7128039 xtensa: fix TLBTEMP_BASE_2 region handling in fast_second_level_miss a91902d xtensa: implement clear_user_highpage and copy_user_highpage 32544d9 xtensa: support aliasing cache in k[un]map_atomic 8504b50 xtensa: support aliasing cache in kmap 270eec7 xtensa: support highmem in aliasing cache flushing code
Highmem support
Done, in the mainline:
6555910 xtensa: add HIGHMEM support
Limit PHY connected to OpenCores MAC to 10/100 MBits/s speeds
Done, in the mainline:
445a48c net: ethoc: don't advertise gigabit speed on attached PHY a13aff0 net: ethoc: set up MII management bus clock
SMP support
Done, in the mainline:
99d5040 xtensa: keep a3 and excsave1 on entry to exception handlers 5515daa xtensa: fix arch spinlock function names 6235153 xtensa: update clockevent setup for SMP cbd1de2 xtensa: move built-in PIC to drivers/irqchip 26a8e96 xtensa: add MX irqchip f615136 xtensa: add SMP support 49b424f xtensa: implement CPU hotplug
Clean up and fix ISS networking
Done, in the mainline:
3f3cd60b xtensa: ISS: clean up iss-network driver 8c8ad85 xtensa: ISS: fix command line parameter name 358b181 xtensa: ISS: init network interface name before the probe 8991fd8 xtensa: ISS: drop IP setup, clean up MAC setup f6ac5a1 xtensa: ISS: enable iss_net_set_mac 35e14b4 xtensa: ISS: always use fixed tuntap config a6e16b9 xtensa: ISS: clean up diagnostic, increase verbosity
oprofile
8c502ca703956e56bf191774e4169752f0f71c8e, 7dd1d39e70769f2dd7a6a508d58b187ed8d1cb95
Done, in the mainline:
e6ffe17 xtensa: add support for oprofile 74f5bf0 xtensa: fix oprofile building as module
simdisk
1a955825662fa378d447b91485d9fe2438124b0a, 8bcbc3adb5c5bfdbd96078c1e68916be859c832d
Done, in the mainline:
b6c7e87 xtensa: ISS: add host file-based simulated disk
Medium level interrupts in less hacky way
489fb47c75772e3a41ef3e988eb0c0e512592085
Done, in the mainline:
2d1c645 xtensa: dispatch medium-priority interrupts 895666a xtensa: disable IRQs while IRQ handler is running
Interrupt management
Done, in the mainline:
2206d5d xtensa: add IRQ domains support
Cache aliasing aware mmap
Done, in the mainline:
de73b6b xtensa: avoid mmap cache aliasing
Atomics (arch/xtensa/include/asm/atomic.h, bitops.h, spinlock.h) and check for S32C1I
Merged in the eb0a9bf31fdbcee9463c0f42fbf4a292ef149a7d, pick up from individual files.
Done, in the mainline:
2f6ea6a xtensa: display s32c1i feature flag in cpuinfo 733536b xtensa: save and restore scompare1 SR on kernel entry c622b29 xtensa: initialize atomctl SR 28570e8 xtensa: add trap_set_handler function 0027312 xtensa: add s32c1i sanity check 219b1e4 xtensa: add s32c1i-based atomic ops implementations e5a9f6a xtensa: add s32c1i-based bitops implementations 71872b5 xtensa: add s32c1i-based spinlock implementations 599bf77 xtensa: fix mb and wmb definitions
Generic kernel_thread & friends
Done, in the mainline:
3306a72 xtensa: switch to generic kernel_thread() f0a1bf0 xtensa: switch to generic kernel_execve() dc241f2 xtensa: switch to generic sys_execve()
Support for Tensilica FPGA boards (xtfpga)
- [+] serial
- [+] ethernet
- [+] FLASH
- [-] audio
In the mainline:
0d456ba xtensa: add support for the XTFPGA boards 5584b4d xtensa: add XTFPGA DTS
Device trees support
Done, in the mainline:
da844a8 xtensa: add device trees support
MMU v3
Done, in the mainline:
e85e335 xtensa: add MMU v3 support 93e294a xtensa: document MMUv3 setup sequence