Commit Graph

130 Commits

Author SHA1 Message Date
Alistair Francis
330d2ae32a target/riscv: Convert the RISC-V exceptions to an enum
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: f191dcf08bf413a822e743a7c7f824d68879a527.1617290165.git.alistair.francis@wdc.com
2021-05-11 20:02:06 +10:00
Atish Patra
ac12b60103 target/riscv: Remove privilege v1.9 specific CSR related code
Qemu doesn't support RISC-V privilege specification v1.9. Remove the
remaining v1.9 specific references from the implementation.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20210319194534.2082397-2-atish.patra@wdc.com>
[Changes by AF:
 - Rebase on latest patches
 - Bump the vmstate_riscv_cpu version_id and minimum_version_id
 ]
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2021-05-11 20:01:10 +10:00
Georg Kotheimer
ec352d0cab target/riscv: Add proper two-stage lookup exception detection
The current two-stage lookup detection in riscv_cpu_do_interrupt falls
short of its purpose, as all it checks is whether two-stage address
translation either via the hypervisor-load store instructions or the
MPRV feature would be allowed.

What we really need instead is whether two-stage address translation was
active when the exception was raised. However, in riscv_cpu_do_interrupt
we do not have the information to reliably detect this. Therefore, when
we raise a memory fault exception we have to record whether two-stage
address translation is active.

Signed-off-by: Georg Kotheimer <georg.kotheimer@kernkonzept.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20210319141459.1196741-1-georg.kotheimer@kernkonzept.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2021-03-22 21:54:40 -04:00
Georg Kotheimer
db9ab38b81 target/riscv: Use background registers also for MSTATUS_MPV
The current condition for the use of background registers only
considers the hypervisor load and store instructions,
but not accesses from M mode via MSTATUS_MPRV+MPV.

Signed-off-by: Georg Kotheimer <georg.kotheimer@kernkonzept.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20210311103036.1401073-1-georg.kotheimer@kernkonzept.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2021-03-22 21:54:40 -04:00
Georg Kotheimer
90ec1cff76 target/riscv: Adjust privilege level for HLV(X)/HSV instructions
According to the specification the "field SPVP of hstatus controls the
privilege level of the access" for the hypervisor virtual-machine load
and store instructions HLV, HLVX and HSV.

Signed-off-by: Georg Kotheimer <georg.kotheimer@kernkonzept.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20210311103005.1400718-1-georg.kotheimer@kernkonzept.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2021-03-22 21:54:40 -04:00
Jim Shu
663e119317 target/riscv: add log of PMP permission checking
Like MMU translation, add qemu log of PMP permission checking for
debugging.

Signed-off-by: Jim Shu <cwshu@andestech.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 1613916082-19528-3-git-send-email-cwshu@andestech.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2021-03-22 21:54:40 -04:00
Jim Shu
b297129ae1 target/riscv: propagate PMP permission to TLB page
Currently, PMP permission checking of TLB page is bypassed if TLB hits
Fix it by propagating PMP permission to TLB page permission.

PMP permission checking also use MMU-style API to change TLB permission
and size.

Signed-off-by: Jim Shu <cwshu@andestech.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 1613916082-19528-2-git-send-email-cwshu@andestech.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2021-03-22 21:54:40 -04:00
Philippe Mathieu-Daudé
6b5fe13786 semihosting: Move include/hw/semihosting/ -> include/semihosting/
We want to move the semihosting code out of hw/ in the next patch.

This patch contains the mechanical steps, created using:

  $ git mv include/hw/semihosting/ include/
  $ sed -i s,hw/semihosting,semihosting, $(git grep -l hw/semihosting)

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210226131356.3964782-2-f4bug@amsat.org>
Message-Id: <20210305135451.15427-2-alex.bennee@linaro.org>
2021-03-10 15:34:12 +00:00
Claudio Fontana
cbc183d2d9 cpu: move cc->transaction_failed to tcg_ops
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

[claudio: wrap target code around CONFIG_TCG and !CONFIG_USER_ONLY]

avoiding its use in headers used by common_ss code (should be poisoned).

Note: need to be careful with the use of CONFIG_USER_ONLY,
Message-Id: <20210204163931.7358-11-cfontana@suse.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-02-05 10:24:14 -10:00
Keith Packard
a10b9d93ec riscv: Add semihosting support
Adapt the arm semihosting support code for RISCV. This implementation
is based on the standard for RISC-V semihosting version 0.2 as
documented in

   https://github.com/riscv/riscv-semihosting-spec/releases/tag/0.2

Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20210107170717.2098982-6-keithp@keithp.com>
Message-Id: <20210108224256.2321-17-alex.bennee@linaro.org>
2021-01-18 10:05:06 +00:00
Alistair Francis
f08c7ff3dc target/riscv: cpu_helper: Remove compile time XLEN checks
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Reviewed-by: Bin Meng <bin.meng@windriver.com>
Tested-by: Bin Meng <bin.meng@windriver.com>
Message-id: 872d2dfcd1c7c3914655d677e911b9432eb8f340.1608142916.git.alistair.francis@wdc.com
2020-12-17 21:56:44 -08:00
Yifei Jiang
c63ca4ff7f target/riscv: Fix the bug of HLVX/HLV/HSV
We found that the hypervisor virtual-machine load and store instructions,
included HLVX/HLV/HSV, couldn't access guest userspace memory.

In the riscv-privileged spec, HLVX/HLV/HSV is defined as follow:
"As usual when V=1, two-stage address translation is applied, and
the HS-level sstatus.SUM is ignored."

But get_physical_address() doesn't ignore sstatus.SUM, when HLVX/HLV/HSV
accesses guest userspace memory. So this patch fixes it.

Signed-off-by: Yifei Jiang <jiangyifei@huawei.com>
Signed-off-by: Yipeng Yin <yinyipeng1@huawei.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20201130012810.899-1-jiangyifei@huawei.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2020-12-17 21:56:43 -08:00
Alistair Francis
1c1c060aa8 target/riscv: Remove the HS_TWO_STAGE flag
The HS_TWO_STAGE flag is no longer required as the MMU index contains
the information if we are performing a two stage access.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: f514b128b1ff0fb41c85f914cee18f905007a922.1604464950.git.alistair.francis@wdc.com
2020-11-09 15:08:53 -08:00
Alistair Francis
c445593d30 target/riscv: Add a virtualised MMU Mode
Add a new MMU mode that includes the current virt mode.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 4b301bc0ea36da962fc1605371b65019ac3073df.1604464950.git.alistair.francis@wdc.com
2020-11-09 15:08:45 -08:00
Yifei Jiang
284d697c74 target/riscv: Merge m/vsstatus and m/vsstatush into one uint64_t unit
mstatus/mstatush and vsstatus/vsstatush are two halved for RISCV32.
This patch expands mstatus and vsstatus to uint64_t instead of
target_ulong so that it can be saved as one unit and reduce some
ifdefs in the code.

Signed-off-by: Yifei Jiang <jiangyifei@huawei.com>
Signed-off-by: Yipeng Yin <yinyipeng1@huawei.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20201026115530.304-2-jiangyifei@huawei.com
2020-11-03 07:17:23 -08:00
Yifei Jiang
33a9a57d2c target/riscv: raise exception to HS-mode at get_physical_address
VS-stage translation at get_physical_address needs to translate pte
address by G-stage translation. But the G-stage translation error
can not be distinguished from VS-stage translation error in
riscv_cpu_tlb_fill. On migration, destination needs to rebuild pte,
and this G-stage translation error must be handled by HS-mode. So
introduce TRANSLATE_STAGE2_FAIL so that riscv_cpu_tlb_fill could
distinguish and raise it to HS-mode.

Signed-off-by: Yifei Jiang <jiangyifei@huawei.com>
Signed-off-by: Yipeng Yin <yinyipeng1@huawei.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20201014101728.848-1-jiangyifei@huawei.com
[ Change by AF:
 - Clarify the fault_pte_addr shift
]
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-22 12:00:22 -07:00
Georg Kotheimer
4aeb9e26c2 target/riscv: Fix update of hstatus.GVA in riscv_cpu_do_interrupt
The hstatus.GVA bit was not set if the faulting guest virtual address
was zero.

Signed-off-by: Georg Kotheimer <georg.kotheimer@kernkonzept.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20201013173054.451135-1-georg.kotheimer@kernkonzept.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-22 12:00:22 -07:00
Georg Kotheimer
ace544532c target/riscv: Fix update of hstatus.SPVP
When trapping from virt into HS mode, hstatus.SPVP was set to
the value of sstatus.SPP, as according to the specification both
flags should be set to the same value.
However, the assignment of SPVP takes place before SPP itself is
updated, which results in SPVP having an outdated value.

Signed-off-by: Georg Kotheimer <georg.kotheimer@kernkonzept.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20201013151054.396481-1-georg.kotheimer@kernkonzept.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-22 12:00:22 -07:00
Alistair Francis
69430111ab riscv: Convert interrupt logs to use qemu_log_mask()
Currently we log interrupts and exceptions using the trace backend in
riscv_cpu_do_interrupt(). We also log exceptions using the interrupt log
mask (-d int) in riscv_raise_exception().

This patch converts riscv_cpu_do_interrupt() to log both interrupts and
exceptions with the interrupt log mask, so that both are printed when a
user runs QEMU with -d int.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 29a8c766c7c4748d0f2711c3a0abb81208138c5e.1601652179.git.alistair.francis@wdc.com
2020-10-22 12:00:22 -07:00
Stefan Hajnoczi
d73415a315 qemu/atomic.h: rename atomic_ to qatomic_
clang's C11 atomic_fetch_*() functions only take a C11 atomic type
pointer argument. QEMU uses direct types (int, etc) and this causes a
compiler error when a QEMU code calls these functions in a source file
that also included <stdatomic.h> via a system header file:

  $ CC=clang CXX=clang++ ./configure ... && make
  ../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid)

Avoid using atomic_*() names in QEMU's atomic.h since that namespace is
used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h
and <stdatomic.h> can co-exist. I checked /usr/include on my machine and
searched GitHub for existing "qatomic_" users but there seem to be none.

This patch was generated using:

  $ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \
    sort -u >/tmp/changed_identifiers
  $ for identifier in $(</tmp/changed_identifiers); do
        sed -i "s%\<$identifier\>%q$identifier%g" \
            $(git grep -I -l "\<$identifier\>")
    done

I manually fixed line-wrap issues and misaligned rST tables.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200923105646.47864-1-stefanha@redhat.com>
2020-09-23 16:07:44 +01:00
Bin Meng
a47ef6e93a hw/riscv: clint: Avoid using hard-coded timebase frequency
At present the CLINT timestamp is using a hard-coded timebase
frequency value SIFIVE_CLINT_TIMEBASE_FREQ. This might not be
true for all boards.

Add a new 'timebase-freq' property to the CLINT device, and
update various functions to accept this as a parameter.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <1598924352-89526-16-git-send-email-bmeng.cn@gmail.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2020-09-09 15:54:19 -07:00
Yifei Jiang
c51a3f5d15 target/riscv: Fix bug in getting trap cause name for trace_riscv_trap
When the cause number is equal to or greater than 23, print "(unknown)" in
trace_riscv_trap. The max valid number of riscv_excp_names is 23, so the last
excpetion "guest_store_page_fault" can not be printed.

In addition, the current check of cause is invalid for riscv_intr_names. So
introduce riscv_cpu_get_trap_name to get the trap cause name.

Signed-off-by: Yifei Jiang <jiangyifei@huawei.com>
Signed-off-by: Yipeng Yin <yinyipeng1@huawei.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20200814035819.1214-1-jiangyifei@huawei.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2020-09-09 15:54:18 -07:00
Alistair Francis
f2d5850f71 target/riscv: Update the Hypervisor trap return/entry
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: e7e4e801234f2934306e734f65860f601a5745bd.1597259519.git.alistair.francis@wdc.com
Message-Id: <e7e4e801234f2934306e734f65860f601a5745bd.1597259519.git.alistair.francis@wdc.com>
2020-08-25 09:11:36 -07:00
Alistair Francis
84b1c04bba target/riscv: Fix the interrupt cause code
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 85b7fdba8abd87adb83275cdc3043ce35a1ed5c3.1597259519.git.alistair.francis@wdc.com
Message-Id: <85b7fdba8abd87adb83275cdc3043ce35a1ed5c3.1597259519.git.alistair.francis@wdc.com>
2020-08-25 09:11:36 -07:00
Alistair Francis
9034e90ad9 target/riscv: Convert MSTATUS MTL to GVA
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 9308432988946de550a68524ed76e4b8683f10e2.1597259519.git.alistair.francis@wdc.com
Message-Id: <9308432988946de550a68524ed76e4b8683f10e2.1597259519.git.alistair.francis@wdc.com>
2020-08-25 09:11:36 -07:00
Alistair Francis
29b3361b14 target/riscv: Do two-stage lookups on hlv/hlvx/hsv instructions
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 024ad8a594fb2feaf0950fbfad1508cfa82ce7f0.1597259519.git.alistair.francis@wdc.com
Message-Id: <024ad8a594fb2feaf0950fbfad1508cfa82ce7f0.1597259519.git.alistair.francis@wdc.com>
2020-08-25 09:11:35 -07:00
Alistair Francis
5a894dd770 target/riscv: Allow setting a two-stage lookup in the virt status
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 08cdefb171b1bdb0c9e3151c509aaadefc3dcd3e.1597259519.git.alistair.francis@wdc.com
Message-Id: <08cdefb171b1bdb0c9e3151c509aaadefc3dcd3e.1597259519.git.alistair.francis@wdc.com>
2020-08-25 09:11:35 -07:00
Zong Li
af3fc195e3 target/riscv: Change the TLB page size depends on PMP entries.
The minimum granularity of PMP is 4 bytes, it is small than 4KB page
size, therefore, the pmp checking would be ignored if its range doesn't
start from the alignment of one page. This patch detects the pmp entries
and sets the small page size to TLB if there is a PMP entry which cover
the page size.

Signed-off-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <6b0bf48662ef26ab4c15381a08e78a74ebd7ca79.1595924470.git.zong.li@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2020-08-21 22:37:55 -07:00
Zong Li
9ef82119b1 target/riscv: Fix the translation of physical address
The real physical address should add the 12 bits page offset. It also
causes the PMP wrong checking due to the minimum granularity of PMP is
4 byte, but we always get the physical address which is 4KB alignment,
that means, we always use the start address of the page to check PMP for
all addresses which in the same page.

Signed-off-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <370a983d0f9e8a9a927b9bb8af5e7bc84b1bf9b1.1595924470.git.zong.li@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2020-08-21 22:37:55 -07:00
Alistair Francis
88914473e7 target/riscv: Report errors validating 2nd-stage PTEs
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2020-06-19 08:24:07 -07:00
Alistair Francis
efe9f9c820 target/riscv: Set access as data_load when validating stage-2 PTEs
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2020-06-19 08:24:07 -07:00
Alistair Francis
1a9540d1f1 target/riscv: Drop support for ISA spec version 1.09.1
The RISC-V ISA spec version 1.09.1 has been deprecated in QEMU since
4.1. It's not commonly used so let's remove support for it.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bin.meng@windriver.com>
2020-06-03 09:11:51 -07:00
Anup Patel
ee79e7cd47 riscv: Fix Stage2 SV32 page table walk
As-per RISC-V H-Extension v0.5 draft, the Stage2 SV32 page table has
12bits of VPN[1] and 10bits of VPN[0]. The additional 2bits in VPN[1]
is required to handle the 34bit intermediate physical address coming
from Stage1 SV32 page table. The 12bits of VPN[1] implies that Stage2
SV32 level-0 page table will be 16KB in size with total 4096 enteries
where each entry maps 4MB of memory (same as Stage1 SV32 page table).

The get_physical_address() function is broken for Stage2 SV32 level-0
page table because it incorrectly computes output physical address for
Stage2 SV32 level-0 page table entry.

The root cause of the issue is that get_physical_address() uses the
"widened" variable to compute level-0 physical address mapping which
changes level-0 mapping size (instead of 4MB). We should use the
"widened" variable only for computing index of Stage2 SV32 level-0
page table.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20200330082724.120444-1-anup.patel@wdc.com
Message-Id: <20200330082724.120444-1-anup.patel@wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2020-04-29 13:16:37 -07:00
Alistair Francis
8f67cd6db7 riscv: AND stage-1 and stage-2 protection flags
Take the result of stage-1 and stage-2 page table walks and AND the two
protection flags together. This way we require both to set permissions
instead of just stage-2.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Anup Patel <anup@brainfault.org>
Message-id: 846f1e18f5922d818bc464ec32c144ef314ec724.1585262586.git.alistair.francis@wdc.com
Message-Id: <846f1e18f5922d818bc464ec32c144ef314ec724.1585262586.git.alistair.francis@wdc.com>
2020-04-29 13:16:37 -07:00
Alistair Francis
3847289054 riscv: Don't use stage-2 PTE lookup protection flags
When doing the fist of a two stage lookup (Hypervisor extensions) don't
set the current protection flags from the second stage lookup of the
base address PTE.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Anup Patel <anup@brainfault.org>
Message-id: 931db85d6890ed4bc2b527fd1011197cd28299aa.1585262586.git.alistair.francis@wdc.com
Message-Id: <931db85d6890ed4bc2b527fd1011197cd28299aa.1585262586.git.alistair.francis@wdc.com>
2020-04-29 13:16:36 -07:00
Rajnesh Kanwal
c5969a3a3c
target/riscv: Fix VS mode interrupts forwarding.
Currently riscv_cpu_local_irq_pending is used to find out pending
interrupt and VS mode interrupts are being shifted to represent
S mode interrupts in this function. So when the cause returned by
this function is passed to riscv_cpu_do_interrupt to actually
forward the interrupt, the VS mode forwarding check does not work
as intended and interrupt is actually forwarded to hypervisor. This
patch fixes this issue.

Signed-off-by: Rajnesh Kanwal <rajnesh.kanwal49@gmail.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-16 17:03:51 -07:00
Anup Patel
c695724868
target/riscv: Emulate TIME CSRs for privileged mode
Currently, TIME CSRs are emulated only for user-only mode. This
patch add TIME CSRs emulation for privileged mode.

For privileged mode, the TIME CSRs will return value provided
by rdtime callback which is registered by QEMU machine/platform
emulation (i.e. CLINT emulation). If rdtime callback is not
available then the monitor (i.e. OpenSBI) will trap-n-emulate
TIME CSRs in software.

We see 25+% performance improvement in hackbench numbers when
TIME CSRs are not trap-n-emulated.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:46:36 -08:00
Alistair Francis
e44b50b5b2
target/riscv: Add the MSTATUS_MPV_ISSET helper macro
Add a helper macro MSTATUS_MPV_ISSET() which will determine if the
MSTATUS_MPV bit is set for both 32-bit and 64-bit RISC-V.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:46:33 -08:00
Alistair Francis
551fa7e8a6
target/riscv: Add support for the 32-bit MSTATUSH CSR
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:46:32 -08:00
Alistair Francis
3067553993
target/riscv: Set htval and mtval2 on execptions
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:46:31 -08:00
Alistair Francis
b2ef6ab9fe
target/riscv: Raise the new execptions when 2nd stage translation fails
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:46:30 -08:00
Alistair Francis
36a18664ba
target/riscv: Implement second stage MMU
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:46:29 -08:00
Alistair Francis
1448689c7b
target/riscv: Allow specifying MMU stage
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:46:28 -08:00
Alistair Francis
29409c1d92
target/riscv: Disable guest FP support based on virtual status
When the Hypervisor extension is in use we only enable floating point
support when both status and vsstatus have enabled floating point
support.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:45:47 -08:00
Alistair Francis
5eb9e782f5
target/riscv: Add hypvervisor trap support
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:45:42 -08:00
Alistair Francis
eccc5a12c2
target/ricsv: Flush the TLB on virtulisation mode changes
To ensure our TLB isn't out-of-date we flush it on all virt mode
changes. Unlike priv mode this isn't saved in the mmu_idx as all
guests share V=1. The easiest option is just to flush on all changes.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:45:40 -08:00
Alistair Francis
3ef10a098b
target/riscv: Add support for virtual interrupt setting
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:45:39 -08:00
Alistair Francis
66e594f280
target/riscv: Add virtual register swapping function
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:45:35 -08:00
Alistair Francis
c7b1bbc80f
target/riscv: Add the force HS exception mode
Add a FORCE_HS_EXCEP mode to the RISC-V virtulisation status. This bit
specifies if an exeption should be taken to HS mode no matter the
current delegation status. This is used when an exeption must be taken
to HS mode, such as when handling interrupts.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:45:29 -08:00
Alistair Francis
ef6bb7b626
target/riscv: Add the virtulisation mode
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:45:28 -08:00
Alistair Francis
ab67a1d07a
target/riscv: Add support for the new execption numbers
The v0.5 Hypervisor spec add new execption numbers, let's add support
for those.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-27 13:45:26 -08:00
Philippe Mathieu-Daudé
dcb32f1d8f tcg: Search includes from the project root source directory
We currently search both the root and the tcg/ directories for tcg
files:

  $ git grep '#include "tcg/' | wc -l
  28

  $ git grep '#include "tcg[^/]' | wc -l
  94

To simplify the preprocessor search path, unify by expliciting the
tcg/ directory.

Patch created mechanically by running:

  $ for x in \
      tcg.h tcg-mo.h tcg-op.h tcg-opc.h \
      tcg-op-gvec.h tcg-gvec-desc.h; do \
    sed -i "s,#include \"$x\",#include \"tcg/$x\"," \
      $(git grep -l "#include \"$x\""); \
    done

Acked-by: David Gibson <david@gibson.dropbear.id.au> (ppc parts)
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200101112303.20724-2-philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2020-01-15 15:13:10 -10:00
Alistair Francis
7ec5d3030b target/riscv: Remove atomic accesses to MIP CSR
Instead of relying on atomics to access the MIP register let's update
our helper function to instead just lock the IO mutex thread before
writing. This follows the same concept as used in PPC for handling
interrupts

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Palmer Dabbelt <palmer@dabbelt.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2019-11-14 09:53:28 -08:00
Giuseppe Musacchio
2921343b3d
linux-user/riscv: Propagate fault address
The CPU loop tagged all the queued signals as QEMU_SI_KILL while it was
filling the `_sigfault` part of `siginfo`: this caused QEMU to copy the
wrong fields over to the userspace program.

Make sure the fault address recorded by the MMU is is stored in the CPU
environment structure.

In case of memory faults store the exception address into `siginfo`.

Signed-off-by: Giuseppe Musacchio <thatlemon@gmail.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-10-28 07:47:27 -07:00
Palmer Dabbelt
37207e1224
RISC-V: Implement cpu_do_transaction_failed
This converts our port over from cpu_do_unassigned_access to
cpu_do_transaction_failed, as cpu_do_unassigned_access has been
deprecated.

Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-10-28 07:47:27 -07:00
Palmer Dabbelt
aacb578fad
RISC-V: Handle bus errors in the page table walker
We directly access physical memory while walking the page tables on
RISC-V, but while doing so we were using cpu_ld*() which does not report
bus errors.  This patch converts the page table walker over to use
address_space_ld*(), which allows bus errors to be detected.

Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-10-28 07:47:27 -07:00
Bin Meng
ddf7813228
riscv: rv32: Root page table address can be larger than 32-bit
For RV32, the root page table's PPN has 22 bits hence its address
bits could be larger than the maximum bits that target_ulong is
able to represent. Use hwaddr instead.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-09-17 08:42:43 -07:00
Alistair Francis
b345b48078
target/riscv: Create function to test if FP is enabled
Let's create a function that tests if floating point support is
enabled. We can then protect all floating point operations based on if
they are enabled.

This patch so far doesn't change anything, it's just preparing for the
Hypervisor support for floating point operations.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Christophe de Dinechin <dinechin@redhat.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-09-17 08:42:42 -07:00
Joel Sing
c13b169f1a
RISC-V: Clear load reservations on context switch and SC
This prevents a load reservation from being placed in one context/process,
then being used in another, resulting in an SC succeeding incorrectly and
breaking atomics.

Signed-off-by: Joel Sing <joel@sing.id.au>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-25 22:37:04 -07:00
Hesham Almatary
db21e6f727
RISC-V: Fix a PMP check with the correct access size
The PMP check should be of the memory access size rather
than TARGET_PAGE_SIZE.

Signed-off-by: Hesham Almatary <Hesham.Almatary@cl.cam.ac.uk>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-23 23:44:42 -07:00
Hesham Almatary
1f447aec78
RISC-V: Check PMP during Page Table Walks
The PMP should be checked when doing a page table walk, and report access
fault exception if the to-be-read PTE failed the PMP check.

Suggested-by: Jonathan Behrens <fintelia@gmail.com>
Signed-off-by: Hesham Almatary <Hesham.Almatary@cl.cam.ac.uk>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-23 23:44:42 -07:00
Hesham Almatary
cc0fdb2985
RISC-V: Check for the effective memory privilege mode during PMP checks
The current PMP check function checks for env->priv which is not the effective
memory privilege mode.

For example, mstatus.MPRV could be set while executing in M-Mode, and in that
case the privilege mode for the PMP check should be S-Mode rather than M-Mode
(in env->priv) if mstatus.MPP == PRV_S.

This patch passes the effective memory privilege mode to the PMP check.
Functions that call the PMP check should pass the correct memory privilege mode
after reading mstatus' MPRV/MPP or hstatus.SPRV (if Hypervisor mode exists).

Suggested-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Hesham Almatary <Hesham.Almatary@cl.cam.ac.uk>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-23 23:44:41 -07:00
Hesham Almatary
635b0b0ea3
RISC-V: Raise access fault exceptions on PMP violations
Section 3.6 in RISC-V v1.10 privilege specification states that PMP violations
report "access exceptions." The current PMP implementation has
a bug which wrongly reports "page exceptions" on PMP violations.

This patch fixes this bug by reporting the correct PMP access exceptions
trap values.

Signed-off-by: Hesham Almatary <Hesham.Almatary@cl.cam.ac.uk>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-23 23:44:41 -07:00
Hesham Almatary
e0f8fa72de
RISC-V: Only Check PMP if MMU translation succeeds
The current implementation unnecessarily checks for PMP even if MMU translation
failed. This may trigger a wrong PMP access exception instead of
a page exception.

For example, the very first instruction fetched after the first satp write in
S-Mode will trigger a PMP access fault instead of an instruction fetch page
fault.

This patch prioritises MMU exceptions over PMP exceptions and only checks for
PMP if MMU translation succeeds. This patch is required for future commits
that properly report PMP exception violations if PTW succeeds.

Signed-off-by: Hesham Almatary <Hesham.Almatary@cl.cam.ac.uk>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-23 23:44:41 -07:00
Michael Clark
cbf5827693
target/riscv: Implement riscv_cpu_unassigned_access
This patch adds support for the riscv_cpu_unassigned_access call
and will raise a load or store access fault.

Signed-off-by: Michael Clark <mjc@sifive.com>
[Changes by AF:
 - Squash two patches and rewrite commit message
 - Set baddr to the access address
]
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-06-23 23:44:41 -07:00
Richard Henderson
3109cd98a6 target/riscv: Use env_cpu, env_archcpu
Cleanup in the boilerplate that each target must define.
Replace riscv_env_get_cpu with env_archcpu.  The combination
CPU(riscv_env_get_cpu) should have used ENV_GET_CPU to begin;
use env_cpu now.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10 07:03:42 -07:00
Alistair Francis
16fdb8ff64
target/riscv: Improve the scause logic
No functional change, just making the code easier to read.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-05-24 12:09:24 -07:00
Alistair Francis
0a01f2eecb
target/riscv: Trigger interrupt on MIP update asynchronously
The requirement of holding the iothread_mutex is burdersome when
swapping the background and foreground registers in the Hypervisor
extension. To avoid the requrirement let's set the interrupt
asynchronously.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-05-24 12:09:24 -07:00
Richard Henderson
c319dc1357 tcg: Use CPUClass::tlb_fill in cputlb.c
We can now use the CPUClass hook instead of a named function.

Create a static tlb_fill function to avoid other changes within
cputlb.c.  This also isolates the asserts within.  Remove the
named tlb_fill function from all of the targets.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-05-10 11:12:50 -07:00
Richard Henderson
8a4ca3c10a target/riscv: Convert to CPUClass::tlb_fill
Note that env->pc is removed from the qemu_log as that value is garbage.
The PC isn't recovered until cpu_restore_state, called from
cpu_loop_exit_restore, called from riscv_raise_exception.

Cc: qemu-riscv@nongnu.org
Cc: Palmer Dabbelt <palmer@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-05-10 11:12:50 -07:00
Michael Clark
d9360e9688
RISC-V: Update load reservation comment in do_interrupt
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Alistair Francis <Alistair.Francis@wdc.com>
Signed-off-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-19 05:14:40 -07:00
Michael Clark
929f0a7fc4
RISC-V: Convert trap debugging to trace events
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Alistair Francis <Alistair.Francis@wdc.com>
Signed-off-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-19 05:14:40 -07:00
Michael Clark
acbbb94e57
RISC-V: Add support for vectored interrupts
If vectored interrupts are enabled (bits[1:0]
of mtvec/stvec == 1) then use the following
logic for trap entry address calculation:

 pc = mtvec + cause * 4

In addition to adding support for vectored interrupts
this patch simplifies the interrupt delivery logic
by making sync/async cause decoding and encoding
steps distinct.

The cause code and the sign bit indicating sync/async
is split at the beginning of the function and fixed
cause is renamed to cause. The MSB setting for async
traps is delayed until setting mcause/scause to allow
redundant variables to be eliminated. Some variables
are renamed for conciseness and moved so that decls
are at the start of the block.

Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Alistair Francis <Alistair.Francis@wdc.com>
Signed-off-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-19 05:14:39 -07:00
Michael Clark
d26f5a4234
RISC-V: Change local interrupts from edge to level
This effectively changes riscv_cpu_update_mip
from edge to level. i.e. cpu_interrupt or
cpu_reset_interrupt are called regardless of
the current interrupt level.

Fixes WFI doesn't return when a IPI is issued:

- https://github.com/riscv/riscv-qemu/issues/132

To test:

1) Apply RISC-V Linux CPU hotplug patch:

- http://lists.infradead.org/pipermail/linux-riscv/2018-May/000603.html

2) Enable CONFIG_CPU_HOTPLUG in linux .config

3) Try to offline and online cpus:

  echo 1 > /sys/devices/system/cpu/cpu2/online
  echo 0 > /sys/devices/system/cpu/cpu2/online
  echo 1 > /sys/devices/system/cpu/cpu2/online

Reported-by: Atish Patra <atishp04@gmail.com>
Cc: Atish Patra <atishp04@gmail.com>
Cc: Alistair Francis <Alistair.Francis@wdc.com>
Signed-off-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-19 05:14:39 -07:00
Michael Clark
e3e7039cc2
RISC-V: Allow interrupt controllers to claim interrupts
We can't allow the supervisor to control SEIP as this would allow the
supervisor to clear a pending external interrupt which will result in
lost a interrupt in the case a PLIC is attached. The SEIP bit must be
hardware controlled when a PLIC is attached.

This logic was previously hard-coded so SEIP was always masked even
if no PLIC was attached. This patch adds riscv_cpu_claim_interrupts
so that the PLIC can register control of SEIP. In the case of models
without a PLIC (spike), the SEIP bit remains software controlled.

This interface allows for hardware control of supervisor timer and
software interrupts by other interrupt controller models.

Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Sagar Karandikar <sagark@eecs.berkeley.edu>
Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Cc: Alistair Francis <Alistair.Francis@wdc.com>
Signed-off-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-19 05:14:39 -07:00
Michael Clark
fb73883964
RISC-V: Use riscv prefix consistently on cpu helpers
* Add riscv prefix to raise_exception function
* Add riscv prefix to CSR read/write functions
* Add riscv prefix to signal handler function
* Add riscv prefix to get fflags function
* Remove redundant declaration of riscv_cpu_init
  and rename cpu_riscv_init to riscv_cpu_init
* rename riscv_set_mode to riscv_cpu_set_mode

Signed-off-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-02-11 15:56:21 -08:00
Michael Clark
a88365c199
RISC-V: Implement existential predicates for CSRs
CSR predicate functions are added to the CSR table.
mstatus.FS and counter enable checks are moved
to predicate functions and two new predicates are
added to check misa.S for s* CSRs and a new PMP
CPU feature for pmp* CSRs.

Processors that don't implement S-mode will trap
on access to s* CSRs and processors that don't
implement PMP will trap on accesses to pmp* CSRs.

PMP checks are disabled in riscv_cpu_handle_mmu_fault
when the PMP CPU feature is not present.

Signed-off-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-09 10:00:56 -08:00
Michael Clark
c7b9517188
RISC-V: Implement modular CSR helper interface
Previous CSR code uses csr_read_helper and csr_write_helper
to update CSR registers however this interface prevents
atomic read/modify/write CSR operations; in addition
there is no trap-free method to access to CSRs due
to the monolithic CSR functions call longjmp.

The current iCSR interface is not safe to be called by
target/riscv/gdbstub.c as privilege checks or missing CSRs
may call longjmp to generate exceptions. It needs to
indicate existence so traps can be generated in the
CSR instruction helpers.

This commit moves CSR access from the monolithic switch
statements in target/riscv/op_helper.c into modular
read/write functions in target/riscv/csr.c using a new
function pointer table for dispatch (which can later
be used to allow CPUs to hook up model specific CSRs).

A read/modify/write interface is added to support atomic
CSR operations and a non-trapping interface is added
to allow exception-free access to CSRs by the debugger.

The CSR functions and CSR dispatch table are ordered
to match The RISC-V Instruction Set Manual, Volume II:
Privileged Architecture Version 1.10, 2.2 CSR Listing.

An API is added to allow derived cpu instances to modify
or implement new CSR operations.

Signed-off-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-08 13:59:09 -08:00
Michael Clark
9543fdaf22
RISC-V: Add hartid and \n to interrupt logging
Add carriage return that was erroneously removed
when converting to qemu_log. Change hard coded
core number to the actual hartid.

Cc: Sagar Karandikar <sagark@eecs.berkeley.edu>
Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Alistair Francis <Alistair.Francis@wdc.com>
Signed-off-by: Michael Clark <mjc@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-12-20 12:08:42 -08:00
Michael Clark
df354dd410
RISC-V: Move non-ops from op_helper to cpu_helper
This patch makes op_helper.c contain only instruction
operation helpers used by translate.c and moves any
unrelated cpu helpers into cpu_helper.c. No logic is
changed by this patch.

Signed-off-by: Michael Clark <mjc@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-17 13:02:14 -07:00