underflow when we have small blocks of memory at the start and end of the
32-bit address range.
While here, only insert mappings pointing at a non-zero amount of memory.
Sponsored by: ABT Systems Ltd
problem affects revision 1xx hardware as well as later versions. Also, the
recommended workaround is to set the PDC count register for a 12-byte
transfer when the actual size is less than that, but there is no need to
extend or zero-out the data buffer, because the blklen register contains
the real transfer size and only that many bytes will be transferred.
Also add a sysctl to turn debugging printfs on or off on the fly.
problem that led to this temporary workaround (and also so I can properly
cite the PR in the commit this time).
In general this is intended to be a temporary workaround until we can figure
out why including any ram from the last megabyte of the physical address
space leads to a NULL pointer deref. Debugging that is made trickier by the
fact that I couldn't even get a backtrace in ddb.
PR: 201614
to generate the phys_avail and dump_avail arrays.
This is a partial fix for the kernel side of the problem mentioned in the
PR. This part handles the cases where comparing start and end addresses of
a block would fail because 32-bit wrap caused the end address to come out
zero if the end of the region is the end of the address space (0xffffffff
with 32-bit vm_paddr_t, but now the code should also work right if we ever
support LPAE with 36-bit addresses).
More work is necessary to make systems with ram at the end of the physical
address space usable, but at least initially it's going to be more like a
workaround than a fix, so this non-hacky part is being committed first.
PR: 201614
providing compiled-in static environment data that is used instead of any
data passed in from a boot loader.
Previously 'env' worked only on i386 and arm xscale systems, because it
required the MD startup code to examine the global envmode variable and
decide whether to use static_env or an environment obtained from the boot
loader, and set the global kern_envp accordingly. Most startup code wasn't
doing so. Making things even more complex, some mips startup code uses an
alternate scheme that involves calling init_static_kenv() to pass an empty
buffer and its size, then uses a series of kern_setenv() calls to populate
that buffer.
Now all MD startup code calls init_static_kenv(), and that routine provides
a single point where envmode is checked and the decision is made whether to
use the compiled-in static_kenv or the values provided by the MD code.
The routine also continues to serve its original purpose for mips; if a
non-zero buffer size is passed the routine installs the empty buffer ready
to accept kern_setenv() values. Now if the size is zero, the provided buffer
full of existing env data is installed. A NULL pointer can be passed if the
boot loader provides no env data; this allows the static env to be installed
if envmode is set to do so.
Most of the work here is a near-mechanical change to call the init function
instead of directly setting kern_envp. A notable exception is in xen/pv.c;
that code was originally installing a buffer full of preformatted env data
along with its non-zero size (like mips code does), which would have allowed
kern_setenv() calls to wipe out the preformatted data. Now it passes a zero
for the size so that the buffer of data it installs is treated as
non-writeable.
- Map all 4GB as VA=PA so that args passed in from a bootloader can
be accessed regardless of where they are.
- Figure out the kernel load address by directly masking the PC rather
then by doing pc-relative math on the _start symbol.
- For EARLY_PRINTF support, map device memory as uncacheable (no-op for
ARM_NEW_PMAP because all TEX types resolve to uncacheable).
Current functionality is somewhat limited: driver assumes that there
is only one active IPU unit (IPU1) and that video output is DI0 and
video mode is 1024x768. For more advanced functionality driver requires
proper clock management which is work in progress. At the moment driver
assumes that pixel clock is configured by u-boot for 1026x768 mode.
Reviewed by: andrew, ian, mmel
Differential Revision: https://reviews.freebsd.org/D4168
into a new function that other platforms can share.
This creates a new ofw_reg_to_paddr() function (in a new ofw_subr.c file)
that contains most of the existing ppc implementation, mostly unchanged.
The ppc code now calls the new MI code from the MD code, then creates a
ppc-specific bus_space mapping from the results. The new arm implementation
does the same in an arm-specific way.
This also moves the declaration of OF_decode_addr() from ofw_machdep.h to
openfirm.h, except on sparc64 which uses a different function signature.
This will help all FDT platforms to set up early console access using
OF_decode_addr().
match the physical load address. Remove the *PHYSADDR symbols which are no
longer necessary.
Also remove a bunch of comments, most of which which have been wrong for
quite some time now, and the rest of which are mooted by these changes. All
that's left in this file is assigning a single symbol to its cannonical
value, not much to comment on anymore.
This eliminates the reliance on PHYSADDR and KERNPHYSADDR compile-time
symbols (except when the rom-copy code is enabled) by using the current
PC and the assumption that the entry-point routine is in the first 1MB
section of the text segment.
Other cleanups done:
- Reduce the initarm() stack size back to 2K. It got increased to
4 * 2K when this file was supporting multicore armv6, but that
support is now in locore-v6.S.
- When building the temporary startup page tables, map the entire
4GB address space as VA=PA before mapping the kernel at its loaded
location. This allows access to boot parameters stored somewhere
in ram by the bootloader, regardless of where that may be.
- When building the page table entry for supporting EARLY_PRINTF, map
the section as uncached unbuffered, since it is presumably device
registers.
Note that this restores the ability to use loader(8)/ubldr on armv4/5
kernels. That was broken in r283035, the point at which ubldr started
loading an arm kernel at any 2MB boundary.
Also note that after this, there is no reason to set KERNVIRTADDR to
anything other than 0xc0000000, and no need for PHYSADDR or KERNPHYSADDR
symbols at all.
Some applications (e.g. Kodi) use tvservice APIs to manage HDMI
modes, power state, EDID etc. directly through VideoCore. After
these manipulations VideoCore may loose its state and needs to be
resynced with ARM. Under Linux this problem is worked around using
fbset utility that recreates framebuffer. Since there is no fbset
utility in FreeBSD we provide sysctl for userland apps to get system
back into normal mode.
The ci20 port (by kan@) is going to reuse almost all of the intrng code
since the SoC in question looks suspiciously like someone took an ARM
SoC design and replaced the ARM core with a MIPS core.
* migrate out the code;
* rename ARM_ -> INTR_;
* rename arm_ -> intr_;
* move the interrupt flush routine from intr.c / intrng.c into
arm/machdep_intr.c - removing the code duplication and removing
the ARM specific bits from here.
Thanks to the Star Wars: The Force Awakens premiere line for allowing
me a couple hours of quiet time to finish the universe builds.
Tested:
* make universe
TODO:
* The structure definitions in subr_intr.c still includes machine/intr.h
which requires one duplicates all of the intrng definitions in
the platform code (which kan has done, and I think we don't have to.)
Instead I should break out the generic things (function declarations,
common intr structures, etc) into a separate header.
* Kan has requested I make the PIC based IPI stuff optional.
I don't know what alternate universe I was inhabiting when I wrote it
originally, but apparently the basic workings of mathematics were different
than in this universe. I also can't explain how it ever worked, except "by
accident", because completely bogus values were being written into the
divisor register.
(1) The pmap argument passed to the function must be current pmap only.
(2) The process must be single threaded as the function is called either
when a process is exiting or from exec_new_vmspace().
Remove pmap_tlb_flush_ng() which is not used anywhere now.
Approved by: kib (mentor)
in pmap_remove_pages().
Some points were considered:
(1) There is no range TLB flush cp15 function.
(2) There is no target selection for hardware TLB flush broadcasting.
(3) Some memory ranges could be mapped sparsely.
(4) Some memory ranges could be quite large.
Tested by buildworld on RPi2 and Jetson TK1, i.e. 4 core platforms.
It turned out that the buildworld time is faster. On the other hand,
when the postponed TLB flush was also removed from pmap_remove_pages(),
the result was worse. But pmap_remove_pages() is called for removing
all user mapping from a process, thus it's quite expected.
Note that the postponed TLB flushes came here from i386 pmap where
hardware TLB flush broadcasting is not available.
Approved by: kib (mentor)
This fixes an issue observed on Cortex A7 (RPi2) and on Cortex A15
(Jetson TK1) causing various memory corruptions. It turned out that
even L2 page table with no valid mapping might be a subject of such
caching.
Note that not all platforms have intermediate TLB caching implemented.
An open question is if this fix is sufficient for all platforms with
this feature.
Approved by: kib (mentor)
These helper functions can be used to read in or write a buffer from or to
an arbitrary process' address space. Without them, this can only be done
using proc_rwmem(), which requires the caller to fill out a uio. This is
onerous and results in code duplication; the new functions provide a simpler
interface which is sufficient for most existing callers of proc_rwmem().
This change also adds a manual page for proc_rwmem() and the new functions.
Reviewed by: jhb, kib
Differential Revision: https://reviews.freebsd.org/D4245
clock_gettime(2) on ARMv7 and ARMv8 systems which have architectural
generic timer hardware. It is similar how the RDTSC timer is used in
userspace on x86.
Fix a permission problem where generic timer access from EL0 (or
userspace on v7) was not properly initialized on APs.
For ARMv7, mark the stack non-executable. The shared page is added for
all arms (including ARMv8 64bit), and the signal trampoline code is
moved to the page.
Reviewed by: andrew
Discussed with: emaste, mmel
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D4209
Boundary Trace to assembly to reduce the overhead of these checks.
Submitted by: Howard Su <howard0su@gmail.com>
Relnotes: Yes
Differential Revision: https://reviews.freebsd.org/D4266
This fixes detection of root interrupt controller for cases,
when interrupt parent is not defined at all or it's not defined directly
in controller node.
Approved by: kib (mentor)
- add new TEX class for WT cacheable memory
- export new TEX class to kernel as VM_MEMATTR_WT attribute
- add new aliases VM_MEMATTR_WRITE_COMBINING and
VM_MEMATTR_WRITE_BACK, it's used in DRM code
Note:
Only Cortex A8 supports WT caching in HW. On rest of Cortex CPUs,
WT requests is treated as uncacheable.
Approved by: kib (mentor)
