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Maciej W. Rozycki ebd729fef3 MIPS: Malta: Fix !EVA SOC-it PCI MMIO
Fix a regression that has caused accesses to the PCI MMIO window to
complete unclaimed in non-EVA configurations with the SOC-it family of
system controllers, preventing PCI devices from working that use MMIO.

In the non-EVA case PHYS_OFFSET is set to 0, meaning that PCI_BAR0 is
set with an empty mask (and PCI_HEAD4 matches addresses starting from 0
accordingly).  Consequently all addresses are matched for incoming DMA
accesses from PCI.  This seems to confuse the system controller's logic
and outgoing bus cycles targeting the PCI MMIO window seem not to make
it to the intended devices.

This happens as well when a wider mask is used with PCI_BAR0, such as
0x80000000 or 0xe0000000, that makes addresses match that overlap with
the PCI MMIO window, which starts at 0x10000000 in our configuration.

Set the mask in PCI_BAR0 to 0xf0000000 for non-EVA then, covering the
non-EVA maximum 256 MiB of RAM, which is what YAMON does and which used
to work correctly up to the offending commit.  Set PCI_P2SCMSKL to match
PCI_BAR0 as required by the system controller's specification, and match
PCI_P2SCMAPL to PCI_HEAD4 for identity mapping.

Verified with:

Core board type/revision =      0x0d (Core74K) / 0x01
System controller/revision =    MIPS SOC-it 101 OCP / 1.3   SDR-FW-4:1
Processor Company ID/options =  0x01 (MIPS Technologies, Inc.) / 0x1c
Processor ID/revision =         0x97 (MIPS 74Kf) / 0x4c

for non-EVA and with:

Core board type/revision =      0x0c (CoreFPGA-5) / 0x00
System controller/revision =    MIPS ROC-it2 / 0.0   FW-1:1 (CLK_unknown) GIC
Processor Company ID/options =  0x01 (MIPS Technologies, Inc.) / 0x00
Processor ID/revision =         0xa0 (MIPS interAptiv UP) / 0x20

for EVA/non-EVA, fixing:

defxx 0000:00:12.0: assign IRQ: got 10
defxx: v1.12 2021/03/10  Lawrence V. Stefani and others
0000:00:12.0: Could not read adapter factory MAC address!

vs:

defxx 0000:00:12.0: assign IRQ: got 10
defxx: v1.12 2021/03/10  Lawrence V. Stefani and others
0000:00:12.0: DEFPA at MMIO addr = 0x10142000, IRQ = 10, Hardware addr = 00-00-f8-xx-xx-xx
0000:00:12.0: registered as fddi0

for non-EVA and causing no change for EVA.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Fixes: 422dd25664 ("MIPS: Malta: Allow PCI devices DMA to lower 2GB physical")
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2025-11-11 12:58:49 +01:00
Documentation gpio fixes for v6.18-rc5 2025-11-07 08:10:55 -08:00
LICENSES LICENSES: Replace the obsolete address of the FSF in the GFDL-1.2 2025-07-24 11:15:39 +02:00
arch MIPS: Malta: Fix !EVA SOC-it PCI MMIO 2025-11-11 12:58:49 +01:00
block block-6.18-20251031 2025-10-31 12:57:19 -07:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto This push contains the following changes: 2025-10-10 08:56:16 -07:00
drivers i2c-for-6.18-rc5 2025-11-09 09:29:44 -08:00
fs three smb client fixes 2025-11-08 10:17:30 -08:00
include Third round of Kbuild fixes for 6.19 2025-11-09 09:22:08 -08:00
init printk changes for 6.18 2025-10-04 11:13:11 -07:00
io_uring io_uring: fix regbuf vector size truncation 2025-11-07 17:17:13 -07:00
ipc namespace-6.18-rc1 2025-09-29 11:20:29 -07:00
kernel Fix a group-throttling bug in the fair scheduler. 2025-11-08 08:59:05 -08:00
lib Crypto library fixes for v6.18-rc5 2025-11-06 12:48:18 -08:00
mm slab fix for 6.18-rc5 2025-11-07 08:01:58 -08:00
net Including fixes from bluetooth and wireless. 2025-11-06 08:52:30 -08:00
rust rust: kbuild: workaround `rustdoc` doctests modifier bug 2025-11-04 00:00:06 +01:00
samples Char/Misc/IIO/Binder changes for 6.18-rc1 2025-10-04 16:26:32 -07:00
scripts kbuild: Let kernel-doc.py use PYTHON3 override 2025-11-08 19:42:22 -07:00
security integrity-v6.18 2025-10-05 10:48:33 -07:00
sound ASoC: Fixes for v6.18 2025-10-30 13:08:08 +01:00
tools iommufd 6.18 first rc pull 2025-11-07 13:13:09 -08:00
usr gen_init_cpio: Ignore fsync() returning EINVAL on pipes 2025-10-07 09:53:05 -07:00
virt KVM x86 fixes for 6.18: 2025-10-18 10:25:43 +02:00
.clang-format memblock: drop for_each_free_mem_pfn_range_in_zone_from() 2025-09-14 08:49:03 +03:00
.clippy.toml rust: clean Rust 1.88.0's warning about `clippy::disallowed_macros` configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: remove Alyssa Rosenzweig 2025-09-18 21:17:31 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore .gitignore: ignore compile_commands.json globally 2025-08-12 15:53:55 -07:00
.mailmap linux_kselftest-kunit-fixes-6.18-rc4 2025-10-30 19:11:27 -07:00
.pylintrc tools: docs: parse-headers.py: move it from sphinx dir 2025-08-29 15:54:42 -06:00
.rustfmt.toml
COPYING
CREDITS MAINTAINERS: mark ISDN subsystem as orphan 2025-10-27 17:49:45 -07:00
Kbuild sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS perf tools fixes for v6.18: 2025-11-06 16:05:33 -08:00
Makefile Linux 6.18-rc5 2025-11-09 15:10:19 -08:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.