[ Upstream commit ae15a41a64 ]
Originally in patch e6d20c55a4 ("openrisc: entry: Fix delay slot
detection") I fixed delay slot detection, but only for QEMU. We missed
that hardware delay slot detection using delay slot exception flag (DSX)
was still broken. This was because QEMU set the DSX flag in both
pre-exception supervision register (ESR) and supervision register (SR)
register, but on real hardware the DSX flag is only set on the SR
register during exceptions.
Fix this by carrying the DSX flag into the SR register during exception.
We also update the DSX flag read locations to read the value from the SR
register not the pt_regs SR register which represents ESR. The ESR
should never have the DSX flag set.
In the process I updated/removed a few comments to match the current
state. Including removing a comment saying that the DSX detection logic
was inefficient and needed to be rewritten.
I have tested this on QEMU with a patch ensuring it matches the hardware
specification.
Link: https://lists.gnu.org/archive/html/qemu-devel/2018-07/msg00000.html
Fixes: e6d20c55a4 ("openrisc: entry: Fix delay slot detection")
Signed-off-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix typos and add the following to the scripts/spelling.txt:
aligment||alignment
I did not touch the "N_BYTE_ALIGMENT" macro in
drivers/net/wireless/realtek/rtlwifi/wifi.h to avoid unpredictable
impact.
I fixed "_aligment_handler" in arch/openrisc/kernel/entry.S because
it is surrounded by #if 0 ... #endif. It is surely safe and I
confirmed "_alignment_handler" is correct.
I also fixed the "controler" I found in the same hunk in
arch/openrisc/kernel/head.S.
Link: http://lkml.kernel.org/r/1481573103-11329-8-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Originally openrisc spec 0 specified that r0 would be wired to ground.
This is no longer the case. r0 is not guaranteed to be 0 at init, so we
need to initialize it to 0 before using it.
Also, if we are clearing r0 we cant use r0 to clear itself. Change the
the CLEAR_GPR macro to use movhi for clearing.
Reported-by: Jakob Viketoft <jakob.viketoft@aacmicrotec.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
These string definitions are no longer used removed them. Noticed this
while working on a CONFIG_DEBUG_INFO build issue.
Signed-off-by: Stafford Horne <shorne@gmail.com>
The strings used during the head/init phase of openrisc bootup were
stored in the executable section of the binary.
This causes compilation to fail when using CONFIG_DEBUG_INFO with
error:
Error: unaligned opcodes detected in executable segment
Signed-off-by: Stafford Horne <shorne@gmail.com>
This brings it inline with the other setup oprations done like the cache
enables _ic_enable and _dc_enable. Also, this is going to make it
easier to initialize additional cpu's when smp is introduced.
Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
[shorne@gmail.com: Added commit body]
Signed-off-by: Stafford Horne <shorne@gmail.com>
The stack size was hard coded to 0x2000, use the standard THREAD_SIZE
definition loaded from thread_info.h.
Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
[shorne@gmail.com: Added body to the commit message]
Signed-off-by: Stafford Horne <shorne@gmail.com>
By slightly reorganizing the code, the number of registers
used in the tlb miss handlers can be reduced by two,
thus removing the need to save them to memory.
Also, some dead and commented out code is removed.
No functional change.
Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Signed-off-by: Stafford Horne <shorne@gmail.com>
vmalloc'ed pages are faulted into a process' page tables on demand. In
order to facilitate this, do_page_fault needs to know whether it was
called via a page fault exception or a TLB-miss exception.
This patch adds a wrapper around the _x_page_fault_handler entry points
that the TLB-miss exceptions can call into in order to have the relevant
parameter set to satisfy do_page_fault.
This fixes a bug and is "good enough" for now. That said, this whole
handling of vmalloc needs to be audited for correctness at some point.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
The kernel might be invoked through the reset vector, so to
preserve parameters passed to it, temp regs that are not
in the function parameter range needs to be used.
Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
This patch enables passing a fdt pointer to the kernel.
This makes for the kernel parameter API:
void kernel(unsigned int fdt);
which, in accordance with the OpenRISC ABI results in:
r3 = pointer to fdt
Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Architecture code and early setup routines for booting Linux.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
