RISC-V privilege spec defines that mtime is exposed as a memory-mapped
machine-mode read-write register. However, as QEMU uses host monotonic
timer as timer source, this makes mtime to be read-only in RISC-V
ACLINT.
This patch makes mtime to be writable by recording the time delta value
between the mtime value to be written and the timer value at the time
mtime is written. Time delta value is then added back whenever the timer
value is retrieved.
Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Jim Shu <jim.shu@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20220420080901.14655-4-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
RISC-V privilege spec defines that:
* In RV32, memory-mapped writes to mtimecmp modify only one 32-bit part
of the register.
* For RV64, naturally aligned 64-bit memory accesses to the mtime and
mtimecmp registers are additionally supported and are atomic.
It's possible to perform both 32/64-bit read/write accesses to both
mtimecmp and mtime registers.
Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Jim Shu <jim.shu@sifive.com>
Message-Id: <20220420080901.14655-3-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
If device's MemoryRegion doesn't have .impl.[min|max]_access_size
declaration, the default access_size_min would be 1 byte and
access_size_max would be 4 bytes (see: softmmu/memory.c).
This will cause a 64-bit memory access to ACLINT to be splitted into
two 32-bit memory accesses.
Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Jim Shu <jim.shu@sifive.com>
Message-Id: <20220420080901.14655-2-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
g_new(T, n) is neater than g_malloc(sizeof(T) * n). It's also safer,
for two reasons. One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.
This commit only touches allocations with size arguments of the form
sizeof(T).
Patch created mechanically with:
$ spatch --in-place --sp-file scripts/coccinelle/use-g_new-etc.cocci \
--macro-file scripts/cocci-macro-file.h FILES...
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20220315144156.1595462-4-armbru@redhat.com>
Reviewed-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
