frequency. This counter can be accessed coherently from both cores.
Use this as the preferred timecounter for the SWARM kernels.
The CP0 COUNT register is unusable as the timecounter on SMP platforms because
the COUNT registers on different CPUs are not guaranteed to be in sync.
when sb_load64() returns.
Some 32-bit arithmetic operations (e.g. subu) have unpredicatable results
when operating on 64-bit registers that are not properly sign-extended.
- We don't need to fall back to uncacheable memory to satisfy BUS_DMA_COHERENT
requests on these CPUs.
- The bus_dmamap_sync() is a no-op for these CPUs.
A side-effect of this change is rename DMAMAP_COHERENT flag to
DMAMAP_UNCACHEABLE. This conveys the purpose of the flag more accurately.
Reviewed by: gonzo, imp
Getting the little-endian PCI bus working on the big-endian CPU proved to be
quite challenging. We let the PCI devices be mapped in the "match byte lanes"
address window. This is where they are mapped by the CFE and DMA transfers
generated to or from addresses within this window are not subject to automatic
byte-swapping.
However any access by the driver to memory-mapped pci space is redirected
via the "match bit lanes" address window. We get the benefit of automatic
byte swapping through this address window and drivers don't need to change
to deal with CPU big-endianness.
this in the Sibyte PCI hostbridge driver instead.
The nexus driver sees resource allocation requests for memory and irq
resources only. These are legitimate resources on all MIPS platforms.
Suggested by: imp
The platform that supports SMP currently is a SWARM with a dual-core Sibyte
processor. The kernel config file to use is SWARM_SMP.
Reviewed by: imp, rrs
The only reason we need to have the sb_load64() and sb_store64()
functions in assembly is to cheat the compiler and generate the
'ld' and 'sd' instructions which it otherwise will not do when
compiling for a 32-bit architecture. There are some 64-bit
registers in the SCD unit that must be accessed using 64-bit
load and store instructions.
This is a workaround for the fact that the CFE is compiled as a 64-bit
application and therefore sets the SR_KX bit every time we call into
it (for e.g. console).
A TLB miss for any address above 0xc0000000 with the SR_KX bit set will
end up at the XTLB exception vector. We workaround this by copying the
standard TLB handler at the XTLB exception vector.
Approved by: imp (mentor)
symbols resolving in DDB
- When zeroing .bss/.sbss do not round end address to page boundary,
it's not neccessary and might destroy data pased by trampoline or
boot loader
interrupt sources feeding into a hardintr anymore. The
mips_mask_hard_irq() function does that for us while an interrupt is
being processed.
Submitted by: neel@
1) Adds future RMI directories
2) Places intr_machdep.c in specfic files.arch pointing to the generic
intr_machdep.c. This allows us to have an architecture dependant intr_machdep.c
(which we will need for RMI) in the machine specific directory
3) removes intr_machdep.c from files.mips
4) Adds some TARGET_XLR_XLS ifdef's for the machine specific intra_machdep.h. We
may need to look at finding a better place to put this. But first I want to
get this thing compiling.
