src/sys/dev/ppc, branch release/12.3.0

i386 4/4G split.

2018-04-13T20:30:49Z

The change makes the user and kernel address spaces on i386 independent, giving each almost the full 4G of usable virtual addresses except for one PDE at top used for trampoline and per-CPU trampoline stacks, and system structures that must be always mapped, namely IDT, GDT, common TSS and LDT, and process-private TSS and LDT if allocated. By using 1:1 mapping for the kernel text and data, it appeared possible to eliminate assembler part of the locore.S which bootstraps initial page table and KPTmap. The code is rewritten in C and moved into the pmap_cold(). The comment in vmparam.h explains the KVA layout. There is no PCID mechanism available in protected mode, so each kernel/user switch forth and back completely flushes the TLB, except for the trampoline PTD region. The TLB invalidations for userspace becomes trivial, because IPI handlers switch page tables. On the other hand, context switches no longer need to reload %cr3. copyout(9) was rewritten to use vm_fault_quick_hold(). An issue for new copyout(9) is compatibility with wiring user buffers around sysctl handlers. This explains two kind of locks for copyout ptes and accounting of the vslock() calls. The vm_fault_quick_hold() AKA slow path, is only tried after the 'fast path' failed, which temporary changes mapping to the userspace and copies the data to/from small per-cpu buffer in the trampoline. If a page fault occurs during the copy, it is short-circuit by exception.s to not even reach C code. The change was motivated by the need to implement the Meltdown mitigation, but instead of KPTI the full split is done. The i386 architecture already shows the sizing problems, in particular, it is impossible to link clang and lld with debugging. I expect that the issues due to the virtual address space limits would only exaggerate and the split gives more liveness to the platform. Tested by: pho Discussed with: bde Sponsored by: The FreeBSD Foundation MFC after: 1 month Differential revision: https://reviews.freebsd.org/D14633

Create a new ISA_PNP_INFO macro. Use this macro every where we have

2017-12-23T06:49:27Z

ISA PNP card support (replace by hand version in if_ed). Move module declarations to the end of some files. Fix PCCARD_PNP_INFO to use nitems(). Remove some stale comments about pc98, turns out the comment was simply wrong.

sys/dev: further adoption of SPDX licensing ID tags.

2017-11-27T14:52:40Z

Mainly focus on files that use BSD 2-Clause license, however the tool I was using misidentified many licenses so this was mostly a manual - error prone - task. The Software Package Data Exchange (SPDX) group provides a specification to make it easier for automated tools to detect and summarize well known opensource licenses. We are gradually adopting the specification, noting that the tags are considered only advisory and do not, in any way, superceed or replace the license texts.

Hide a normal probe warning message under bootverbose, similar to atkbdc

2017-09-18T18:42:28Z

Add PCI Id for MosChip MCS9900.

2017-08-27T11:37:07Z

Submitted by: Robert Clausecker PR: 214670 MFC after: 1 week

Remove register keyword from sys/ and ANSIfy prototypes

2017-05-17T00:34:34Z

A long long time ago the register keyword told the compiler to store the corresponding variable in a CPU register, but it is not relevant for any compiler used in the FreeBSD world today. ANSIfy related prototypes while here. Reviewed by: cem, jhb Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D10193

sys/dev: Replace zero with NULL for pointers.

2017-02-20T03:43:12Z

Makes things easier to read, plus architectures may set NULL to something different than zero. Found with: devel/coccinelle MFC after: 3 weeks

Remove pc98 support completely.

2017-01-28T02:22:15Z

I thank all developers and contributors for pc98. Relnotes: yes

Use uintmax_t (typedef'd to rman_res_t type) for rman ranges.

2016-03-18T01:28:41Z

On some architectures, u_long isn't large enough for resource definitions. Particularly, powerpc and arm allow 36-bit (or larger) physical addresses, but type `long' is only 32-bit. This extends rman's resources to uintmax_t. With this change, any resource can feasibly be placed anywhere in physical memory (within the constraints of the driver). Why uintmax_t and not something machine dependent, or uint64_t? Though it's possible for uintmax_t to grow, it's highly unlikely it will become 128-bit on 32-bit architectures. 64-bit architectures should have plenty of RAM to absorb the increase on resource sizes if and when this occurs, and the number of resources on memory-constrained systems should be sufficiently small as to not pose a drastic overhead. That being said, uintmax_t was chosen for source clarity. If it's specified as uint64_t, all printf()-like calls would either need casts to uintmax_t, or be littered with PRI*64 macros. Casts to uintmax_t aren't horrible, but it would also bake into the API for resource_list_print_type() either a hidden assumption that entries get cast to uintmax_t for printing, or these calls would need the PRI*64 macros. Since source code is meant to be read more often than written, I chose the clearest path of simply using uintmax_t. Tested on a PowerPC p5020-based board, which places all device resources in 0xfxxxxxxxx, and has 8GB RAM. Regression tested on qemu-system-i386 Regression tested on qemu-system-mips (malta profile) Tested PAE and devinfo on virtualbox (live CD) Special thanks to bz for his testing on ARM. Reviewed By: bz, jhb (previous) Relnotes: Yes Sponsored by: Alex Perez/Inertial Computing Differential Revision: https://reviews.freebsd.org/D4544

Migrate many bus_alloc_resource() calls to bus_alloc_resource_anywhere().

2016-02-27T03:38:01Z

Most calls to bus_alloc_resource() use "anywhere" as the range, with a given count. Migrate these to use the new bus_alloc_resource_anywhere() API. Reviewed by: jhb Differential Revision: https://reviews.freebsd.org/D5370