The prior accesses to the descriptor rings & init block via cached
memory had a few issues:
- The memory needs cache flushes or invalidation at the appropriate
times, but was not necessarily aligned on cache line boundaries.
This could lead to data being incorrectly lost or written back to
RAM at the wrong time.
- There are points where ordering of writes to the memory is
important, but because it's cached memory the pcnet controller
would see cache lines written back ordered by address. This could
occasionally lead to hardware seeing descriptors in an incorrect
state.
- Flushing the cache constantly is inefficient.
So, to avoid all of those issues simply access the descriptors & init
block via uncached memory. The MIPS-specific UNCACHED_SDRAM macro is
used to do this (retrieving an address in kseg1) as I could see no
existing generic solution. Since the MIPS Malta board is the only user
of the pcnet driver, hopefully this doesn't matter.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
The MPC824x processors have long reached EOL, and the PN62 board has
not seen any board-specific updates for more than a decade. It is now
causing build issues. Instead of wasting time on things nobody is
interested in any more, we rather drop this board.
Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Wolfgang Grandegger <wg@grandegger.com>
cc: Tom Rini <trini@ti.com>
On relatively slow boards (such as the MIPS Malta with an FPGA core
card) it can be extremely common for transmits to underflow - to the
point where it appears they simply do not work at all. Setting the
NOUFLO bit causes the ethernet controller to not begin transmission on
the wire until a transmit start point is reached. Setting that transmit
start point to the full packet will cause the controller to only
transmit the packet once it has buffered it entirely thus preventing any
transmit underflows from occuring and allowing the controller to
function on slower boards.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Ensure that the view of memory from the CPU & the ethernet controller is
coherent at the various points where they exchange data. This prevents
stale data from being transmitted or received, and prevents the driver
from getting stuck waiting for the ethernet controller to update
descriptors when in reality it has but the old values are being read
from cache.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fix up the code to match Documentation/CodingStyle. This is mostly
removing extraneous spaces.
No functional change is intended.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
The pcnet driver uses the pci_phys_to_mem function
to get the memory address of the DMA buffers. This
This assumes an 1:1 mapping between the PCI and
physical memory which is not true on all platforms.
On MIPS platform U-Boot is running within a mapped
memory region, and the pci_phys_to_mem macro can't
be used to obtain the memory address of the buffers.
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
Fix this:
pcnet.c: In function 'pcnet_initialize':
pcnet.c:224:13: warning: assignment from incompatible pointer type
Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Fix:
pcnet.c: In function 'pcnet_probe':
pcnet.c:247:8: warning: variable 'chipname' set but not used
[-Wunused-but-set-variable]
Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Wolfgang Grandegger <wg@denx.de>
pcnet driver does not have write_hwaddr function.
However, eth stuff executes write_hwaddr function
because eth_device structure has not been initialized.
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
CC: Ben Warren <biggerbadderben@gmail.com>
Change return values of init() functions in all Ethernet drivers to conform
to the following:
>=0: Success
<0: Failure
All drivers going forward should return 0 on success. Current drivers that
return 1 on success were left as-is to minimize changes.
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>
Acked-by: Stefan Roese <sr@denx.de>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Kim Phillips <kim.phillips@freescale.com>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Acked-By: Timur Tabi <timur@freescale.com>
