Commit graph

294 commits

Author SHA1 Message Date
Jay Chang
86bc3a0abf target/riscv: Restrict midelegh access to S-mode harts
RISC-V AIA Spec states:
"For a machine-level environment, extension Smaia encompasses all added
CSRs and all modifications to interrupt response behavior that the AIA
specifies for a hart, over all privilege levels. For a supervisor-level
environment, extension Ssaia is essentially the same as Smaia except
excluding the machine-level CSRs and behavior not directly visible to
supervisor level."

Since midelegh is an AIA machine-mode CSR, add Smaia extension check in
aia_smode32 predicate.

Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Jay Chang <jay.chang@sifive.com>
Reviewed-by: Nutty Liu<liujingqi@lanxincomputing.com>
Message-ID: <20250701030021.99218-3-jay.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-07-30 10:59:26 +10:00
Jay Chang
e443ba0336 target/riscv: Restrict mideleg/medeleg/medelegh access to S-mode harts
RISC-V Privileged Spec states:
"In harts with S-mode, the medeleg and mideleg registers must exist, and
setting a bit in medeleg or mideleg will delegate the corresponding trap
, when occurring in S-mode or U-mode, to the S-mode trap handler. In
harts without S-mode, the medeleg and mideleg registers should not
exist."

Add smode predicate to ensure these CSRs are only accessible when S-mode
is supported.

Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Jay Chang <jay.chang@sifive.com>
Reviewed-by: Nutty Liu<liujingqi@lanxincomputing.com>
Message-ID: <20250701030021.99218-2-jay.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-07-30 10:59:26 +10:00
Xu Lu
30ef718423 target/riscv: Fix exception type when VU accesses supervisor CSRs
When supervisor CSRs are accessed from VU-mode, a virtual instruction
exception should be raised instead of an illegal instruction.

Fixes: c1fbcecb3a (target/riscv: Fix csr number based privilege checking)
Signed-off-by: Xu Lu <luxu.kernel@bytedance.com>
Reviewed-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Nutty Liu <liujingqi@lanxincomputing.com>
Message-ID: <20250708060720.7030-1-luxu.kernel@bytedance.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-07-30 10:59:26 +10:00
Charalampos Mitrodimas
b3452452e6 target/riscv: Fix MEPC/SEPC bit masking for IALIGN
According to the RISC-V Privileged Architecture specification, the low
bit of MEPC/SEPC must always be zero. When IALIGN=32, the two low bits
must be zero.

This commit fixes the behavior of MEPC/SEPC CSR reads and writes, and
the implicit reads by MRET/SRET instructions to properly mask the
lowest bit(s) based on whether the C extension is enabled:
- When C extension is enabled (IALIGN=16): mask bit 0
- When C extension is disabled (IALIGN=32): mask bits [1:0]

Previously, when vectored mode bits from STVEC (which sets bit 0 for
vectored mode) were written to MEPC, the bits would not be cleared
correctly, causing incorrect behavior on MRET.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2855
Signed-off-by: Charalampos Mitrodimas <charmitro@posteo.net>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20250703182157.281320-2-charmitro@posteo.net>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-07-04 21:09:49 +10:00
Jay Chang
cd633bea8b target/riscv: Make PMP region count configurable
Previously, the number of PMP regions was hardcoded to 16 in QEMU.
This patch replaces the fixed value with a new `pmp_regions` field,
allowing platforms to configure the number of PMP regions.

If no specific value is provided, the default number of PMP regions
remains 16 to preserve the existing behavior.

A new CPU parameter num-pmp-regions has been introduced to the QEMU
command line. For example:

	-cpu rv64, g=true, c=true, pmp=true, num-pmp-regions=8

Signed-off-by: Jay Chang <jay.chang@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250606072525.17313-3-jay.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-07-04 21:09:48 +10:00
Jay Chang
444cffd37b target/riscv: Extend PMP region up to 64
According to the RISC-V Privileged Specification (version >1.12),
RV32 supports 16 CSRs (pmpcfg0–pmpcfg15) to configure 64 PMP regions
(pmpaddr0–pmpaddr63).

Signed-off-by: Jay Chang <jay.chang@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20250522081236.4050-2-jay.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-07-04 21:09:48 +10:00
Jim Shu
dff5f51540 target/riscv: Enable/Disable S/VS-mode Timer when STCE bit is changed
Updating STCE will enable/disable SSTC in S-mode or/and VS-mode, so we
also need to update S/VS-mode Timer and S/VSTIP bits in $mip CSR.

Signed-off-by: Jim Shu <jim.shu@sifive.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250519143518.11086-5-jim.shu@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-07-04 21:09:48 +10:00
Jim Shu
3cb2edae74 target/riscv: Fix VSTIP bit in sstc extension.
VSTIP is only writable when both [mh]envcfg.STCE is enabled, or it will
revert it's defined behavior as if sstc extension is not implemented.

Signed-off-by: Jim Shu <jim.shu@sifive.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250519143518.11086-4-jim.shu@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-07-04 21:09:48 +10:00
Paolo Bonzini
1016b0364f target/riscv: generalize custom CSR functionality
While at it, constify it so that the RISCVCSR array in RISCVCPUDef
can also be const.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-20 08:18:53 +02:00
Paolo Bonzini
211c7f9bb8 target/riscv: update max_satp_mode based on QOM properties
Almost all users of cpu->cfg.satp_mode care about the "max" value
satp_mode_max_from_map(cpu->cfg.satp_mode.map).  Convert the QOM
properties back into it.  For TCG, deduce the bitmap of supported modes
from valid_vm[].

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-20 08:04:19 +02:00
Richard Henderson
7b069906b6 target/riscv: Fix write_misa vs aligned next_pc
Do not examine a random host return address, but
properly compute the next pc for the guest cpu.

Fixes: f18637cd61 ("RISC-V: Add misa runtime write support")
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20250425152311.804338-8-richard.henderson@linaro.org>
[ Changes by AF:
 - Change `& ~3` to `& 3`
]
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-05-19 13:39:29 +10:00
Richard Henderson
9ef792a78d target/riscv: Pass ra to riscv_csrrw_i128
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20250425152311.804338-6-richard.henderson@linaro.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-05-19 13:39:29 +10:00
Richard Henderson
f1304836ea target/riscv: Pass ra to riscv_csrrw
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20250425152311.804338-5-richard.henderson@linaro.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-05-19 13:39:29 +10:00
Richard Henderson
c26c4afd0f target/riscv: Pass ra to riscv_csrrw_do128
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20250425152311.804338-4-richard.henderson@linaro.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-05-19 13:39:29 +10:00
Richard Henderson
bfc7936f42 target/riscv: Pass ra to riscv_csrrw_do64
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20250425152311.804338-3-richard.henderson@linaro.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-05-19 13:39:29 +10:00
Richard Henderson
6c8954cb35 target/riscv: Pass ra to riscv_csr_write_fn
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20250425152311.804338-2-richard.henderson@linaro.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-05-19 13:39:29 +10:00
Philippe Mathieu-Daudé
84307cd602 include: Remove 'exec/exec-all.h'
"exec/exec-all.h" is now fully empty, let's remove it.

Mechanical change running:

  $ sed -i '/exec\/exec-all.h/d' $(git grep -wl exec/exec-all.h)

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Mark Cave-Ayland <mark.caveayland@nutanix.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20250424202412.91612-14-philmd@linaro.org>
2025-04-30 12:45:05 -07:00
Philippe Mathieu-Daudé
0f81774dd1 target/riscv: Include missing 'accel/tcg/getpc.h' in csr.c
"accel/tcg/getpc.h" is pulled in indirectly. Include it
explicitly to avoid when refactoring unrelated headers:

  target/riscv/csr.c:2117:25: error: call to undeclared function 'GETPC' [-Wimplicit-function-declaration]
   2117 |     if ((val & RVC) && (GETPC() & ~3) != 0) {
        |                         ^

Note the TODO comment around GETPC() added upon introduction in
commit f18637cd61 ("RISC-V: Add misa runtime write support"):

 2099 static RISCVException write_misa(CPURISCVState *env, int csrno,
 2100                                  target_ulong val)
 2101 {
  ...
 2113     /*
 2114      * Suppress 'C' if next instruction is not aligned
 2115      * TODO: this should check next_pc
 2116      */
 2117     if ((val & RVC) && (GETPC() & ~3) != 0) {
 2118         val &= ~RVC;
 2119     }

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Mark Cave-Ayland <mark.caveayland@nutanix.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20250424202412.91612-8-philmd@linaro.org>
2025-04-30 12:45:05 -07:00
Richard Henderson
161f5bc8e9 include/exec: Split out icount.h
Split icount stuff from system/cpu-timers.h.
There are 17 files which only require icount.h, 7 that only
require cpu-timers.h, and 7 that require both.

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2025-04-23 14:08:44 -07:00
Daniel Henrique Barboza
ec6411a525 target/riscv/csr.c: fix OVERFLOW_BEFORE_WIDEN in rmw_sctrdepth()
Coverity found the following issue:

  >>>     CID 1593156:  Integer handling issues  (OVERFLOW_BEFORE_WIDEN)
  >>>     Potentially overflowing expression "0x10 << depth" with type
  "int" (32 bits, signed) is evaluated using 32-bit arithmetic, and then
  used in a context that expects an expression of type "uint64_t" (64
  bits, unsigned).
  4299             depth = 16 << depth;

Fix it by forcing the expression to be 64 bits wide by using '16ULL'.

Resolves: Coverity CID 1593156
Fixes: c48bd18eae ("target/riscv: Add support for Control Transfer Records extension CSRs.")
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250307124602.1905754-1-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-03-19 16:37:24 +10:00
Deepak Gupta
86c78b2806 target/riscv: fix access permission checks for CSR_SSP
Commit:8205bc1 ("target/riscv: introduce ssp and enabling controls for
zicfiss") introduced CSR_SSP but it mis-interpreted the spec on access
to CSR_SSP in M-mode. Gated to CSR_SSP is not gated via `xSSE`. But
rather rules clearly specified in section "22.2.1. Shadow Stack Pointer
(ssp) CSR access contr" in the priv spec.

Fixes: 8205bc127a ("target/riscv: introduce ssp and enabling controls
for zicfiss". Thanks to Adam Zabrocki for bringing this to attention.

Reported-by: Adam Zabrocki <azabrocki@nvidia.com>
Signed-off-by: Deepak Gupta <debug@rivosinc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250306064636.452396-1-debug@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-03-19 16:33:01 +10:00
Philippe Mathieu-Daudé
6ff5da1600 exec: Declare tlb_flush*() in 'exec/cputlb.h'
Move CPU TLB related methods to "exec/cputlb.h".

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-ID: <20241114011310.3615-19-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2025-03-08 07:56:14 -08:00
Rajnesh Kanwal
8b65852196 target/riscv: Add support to access ctrsource, ctrtarget, ctrdata regs.
CTR entries are accessed using ctrsource, ctrtarget and ctrdata
registers using smcsrind/sscsrind extension. This commits extends
the csrind extension to support CTR registers.

ctrsource is accessible through xireg CSR, ctrtarget is accessible
through xireg1 and ctrdata is accessible through xireg2 CSR.

CTR supports maximum depth of 256 entries which are accessed using
xiselect range 0x200 to 0x2ff.

This commits also adds properties to enable CTR extension. CTR can be
enabled using smctr=true and ssctr=true now.

Signed-off-by: Rajnesh Kanwal <rkanwal@rivosinc.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250212-b4-ctr_upstream_v6-v7-1-4e8159ea33bf@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-03-04 15:42:54 +10:00
Rajnesh Kanwal
c48bd18eae target/riscv: Add support for Control Transfer Records extension CSRs.
This commit adds support for [m|s|vs]ctrcontrol, sctrstatus and
sctrdepth CSRs handling.

Signed-off-by: Rajnesh Kanwal <rkanwal@rivosinc.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250205-b4-ctr_upstream_v6-v6-3-439d8e06c8ef@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-03-04 15:42:54 +10:00
Daniel Henrique Barboza
485eb79989 target/riscv/csr.c: fix deadcode in aia_smode32()
Coverity reported a DEADCODE ticket in this function, as follows:

 >>>>      CID 1590358:  Control flow issues  (DEADCODE)
 >>>>      Execution cannot reach this statement: "return ret;".
 > 380             return ret;
 > 381         }

The cause is that the 'if (ret != RISCV_EXCP_NONE)' conditional is
duplicated:

    ret = smstateen_acc_ok(env, 0, SMSTATEEN0_AIA);
    if (ret != RISCV_EXCP_NONE) {
        return ret;
    }

    if (ret != RISCV_EXCP_NONE) {
        return ret;
    }

Remove the duplication to fix the deadcode.

Resolves: Coverity CID 1590358
Fixes: dbcb6e1ccf ("target/riscv: Enable S*stateen bits for AIA")
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250121184847.2109128-5-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-03-04 15:42:53 +10:00
Daniel Henrique Barboza
c1edd5f756 target/riscv/csr.c: fix deadcode in rmw_xiregi()
Coverity found a DEADCODE issue in rmw_xiregi() claiming that we can't
reach 'RISCV_EXCP_VIRT_INSTRUCTION_FAULT' at the 'done' label:

 > 2652     done:
 >>>>      CID 1590357:  Control flow issues  (DEADCODE)
 >>>>      Execution cannot reach the expression "RISCV_EXCP_VIRT_INSTRUCTION_FAULT"
     inside this statement: "return (env->virt_enabled &...".
 > 2653         return (env->virt_enabled && virt) ?
 > 2654                 RISCV_EXCP_VIRT_INSTRUCTION_FAULT : RISCV_EXCP_ILLEGAL_INST;

This happens because 'virt' is being set to 'false' and it will remain
as 'false' in any code path where 'done' will be called. The label can
be safely reduced to:

done:
     return RISCV_EXCP_ILLEGAL_INST;

And that will leave us with the following usage of a 'goto' skipping a
single 'return' to do another single 'return':

     } else {
        goto done;
     }

     return rmw_xireg_csrind(env, csrno, isel, val, new_val, wr_mask);

done:
     return RISCV_EXCP_ILLEGAL_INST;

Which we will eliminate it and just do 'return RISCV_EXCP_ILLEGAL_INST'
instead.

Resolves: Coverity CID 1590357
Fixes: 5e33a20827 ("target/riscv: Support generic CSR indirect access")
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250121184847.2109128-4-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-03-04 15:42:53 +10:00
Daniel Henrique Barboza
e07a89143b target/riscv/csr.c: fix 'ret' deadcode in rmw_xireg()
Coverity found a second DEADCODE issue in rmw_xireg() claiming that we can't
reach 'RISCV_EXCP_NONE' at the 'done' label:

 > 2706     done:
 > 2707         if (ret) {
 > 2708             return (env->virt_enabled && virt) ?
 > 2709                    RISCV_EXCP_VIRT_INSTRUCTION_FAULT : RISCV_EXCP_ILLEGAL_INST;
 > 2710         }
 >>>>      CID 1590356:  Control flow issues  (DEADCODE)
 >>>>      Execution cannot reach this statement: "return RISCV_EXCP_NONE;".
 > 2711         return RISCV_EXCP_NONE;

Our label is now reduced after fixing another deadcode in the previous
patch but the problem reported here still remains:

 done:
    if (ret) {
        return RISCV_EXCP_ILLEGAL_INST;
    }
    return RISCV_EXCP_NONE;

This happens because 'ret' changes only once at the start of the
function:

    ret = smstateen_acc_ok(env, 0, SMSTATEEN0_SVSLCT);
    if (ret != RISCV_EXCP_NONE) {
        return ret;
    }

So it's a guarantee that ret will be RISCV_EXCP_NONE (-1) if we ever
reach the label, i.e. "if (ret)" will always be true, and  the label can
be even further reduced to:

done:
    return RISCV_EXCP_ILLEGAL_INST;

To make a better use of the label, remove the 'else' from the
xiselect_aia_range() chain and let it fall-through to the 'done' label
since they are now both returning RISCV_EXCP_ILLEGAL_INST.

Resolves: Coverity CID 1590356
Fixes: dc0280723d ("target/riscv: Decouple AIA processing from xiselect and xireg")
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250121184847.2109128-3-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-03-04 15:42:53 +10:00
Daniel Henrique Barboza
bf031e257d target/riscv/csr.c: fix deadcode in rmw_xireg()
Coverity found a DEADCODE issue in rmw_xireg() claiming that we can't
reach 'RISCV_EXCP_VIRT_INSTRUCTION_FAULT' at the 'done' label:

done:
    if (ret) {
        return (env->virt_enabled && virt) ?
               RISCV_EXCP_VIRT_INSTRUCTION_FAULT : RISCV_EXCP_ILLEGAL_INST;
    }
    return RISCV_EXCP_NONE;

This happens because the 'virt' flag, which is only used by 'done', is
set to 'false' and it will always remain 'false' in any condition where
we'll jump to 'done':

    switch (csrno) {
    (...)
    case CSR_VSIREG:
        isel = env->vsiselect;
        virt = true;
        break;
    default:
        goto done;
    };

'virt = true' will never reach 'done' because we have a if/else-if/else
block right before the label that will always return:

    if (xiselect_aia_range(isel)) {
        return ...
    } else if (...) {
        return ...
    } else {
        return RISCV_EXCP_ILLEGAL_INST;
    }

All this means that we can preserve the current logic by reducing the
'done' label to:

done:
    if (ret) {
        return RISCV_EXCP_ILLEGAL_INST;
    }
    return RISCV_EXCP_NONE;

The flag 'virt' is now unused. Remove it.

Fix the 'goto done' identation while we're at it.

Resolves: Coverity CID 1590359
Fixes: dc0280723d ("target/riscv: Decouple AIA processing from xiselect and xireg")
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250121184847.2109128-2-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-03-04 15:42:53 +10:00
Clément Léger
d2e92f1c6d target/riscv: Add Smdbltrp CSRs handling
Add `ext_smdbltrp`in RISCVCPUConfig and implement MSTATUS.MDT behavior.
Also set MDT to 1 at reset according to the specification.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250110125441.3208676-7-cleger@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-01-19 09:44:35 +10:00
Clément Léger
0aadf8162a target/riscv: Add Ssdbltrp CSRs handling
Add ext_ssdbltrp in RISCVCPUConfig and implement MSTATUS.SDT,
{H|M}ENVCFG.DTE and modify the availability of MTVAL2 based on the
presence of the Ssdbltrp ISA extension.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250110125441.3208676-3-cleger@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-01-19 09:44:35 +10:00
Clément Léger
507957eb2a target/riscv: Fix henvcfg potentially containing stale bits
With the current implementation, if we had the following scenario:
- Set bit x in menvcfg
- Set bit x in henvcfg
- Clear bit x in menvcfg
then, the internal variable env->henvcfg would still contain bit x due
to both a wrong menvcfg mask used in write_henvcfg() as well as a
missing update of henvcfg upon menvcfg update.
This can lead to some wrong interpretation of the context. In order to
update henvcfg upon menvcfg writing, call write_henvcfg() after writing
menvcfg. Clearing henvcfg upon writing the new value is also needed in
write_henvcfg() as well as clearing henvcfg upper part when writing it
with write_henvcfgh().

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250110125441.3208676-2-cleger@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-01-19 09:44:35 +10:00
Kaiwen Xue
6247dc2ef7 target/riscv: Add counter delegation/configuration support
The Smcdeleg/Ssccfg adds the support for counter delegation via
S*indcsr and Ssccfg.

It also adds a new shadow CSR scountinhibit and menvcfg enable bit (CDE)
to enable this extension and scountovf virtualization.

Signed-off-by: Kaiwen Xue <kaiwenx@rivosinc.com>
Co-developed-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Message-ID: <20250110-counter_delegation-v5-8-e83d797ae294@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-01-19 09:44:35 +10:00
Kaiwen Xue
b6504cd0d1 target/riscv: Add select value range check for counter delegation
This adds checks in ops performed on xireg and xireg2-xireg6 so that the
counter delegation function will receive a valid xiselect value with the
proper extensions enabled.

Co-developed-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Kaiwen Xue <kaiwenx@rivosinc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Message-ID: <20250110-counter_delegation-v5-7-e83d797ae294@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-01-19 09:44:35 +10:00
Kaiwen Xue
5e33a20827 target/riscv: Support generic CSR indirect access
This adds the indirect access registers required by sscsrind/smcsrind
and the operations on them. Note that xiselect and xireg are used for
both AIA and sxcsrind, and the behavior of accessing them depends on
whether each extension is enabled and the value stored in xiselect.

Co-developed-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Kaiwen Xue <kaiwenx@rivosinc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Message-ID: <20250110-counter_delegation-v5-4-e83d797ae294@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-01-19 09:44:35 +10:00
Atish Patra
dbcb6e1ccf target/riscv: Enable S*stateen bits for AIA
As per the ratified AIA spec v1.0, three stateen bits control AIA CSR
access.

Bit 60 controls the indirect CSRs
Bit 59 controls the most AIA CSR state
Bit 58 controls the IMSIC state such as stopei and vstopei

Enable the corresponding bits in [m|h]stateen and enable corresponding
checks in the CSR accessor functions.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Message-ID: <20250110-counter_delegation-v5-3-e83d797ae294@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-01-19 09:44:35 +10:00
Kaiwen Xue
dc0280723d target/riscv: Decouple AIA processing from xiselect and xireg
Since xiselect and xireg also will be of use in sxcsrind, AIA should
have its own separated interface when those CSRs are accessed.

Signed-off-by: Kaiwen Xue <kaiwenx@rivosinc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Message-ID: <20250110-counter_delegation-v5-2-e83d797ae294@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-01-19 09:44:35 +10:00
Tommy Wu
5db557f82b target/riscv: Add Smrnmi CSRs
The Smrnmi extension adds the 'mnscratch', 'mnepc', 'mncause',
'mnstatus' CSRs.

Signed-off-by: Frank Chang <frank.chang@sifive.com>
Signed-off-by: Tommy Wu <tommy.wu@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250106054336.1878291-3-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-01-19 09:44:34 +10:00
Alexey Baturo
33ca99a111 target/riscv: Add new CSR fields for S{sn, mn, m}pm extensions as part of Zjpm v1.0
Signed-off-by: Alexey Baturo <baturo.alexey@gmail.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250106102346.1100149-3-baturo.alexey@gmail.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-01-19 09:44:34 +10:00
Alexey Baturo
37089cb8ad target/riscv: Remove obsolete pointer masking extension code.
Zjpm extension is finally ratified. And it's much simplier compared to the experimental one.
The newer version doesn't allow to specify custom mask or base for pointer masking.
Instead it allows only certain options for masking top bits.

Signed-off-by: Alexey Baturo <baturo.alexey@gmail.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250106102346.1100149-2-baturo.alexey@gmail.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2025-01-19 09:44:34 +10:00
Stefan Hajnoczi
65cb7129f4 Accel & Exec patch queue
- Ignore writes to CNTP_CTL_EL0 on HVF ARM (Alexander)
 - Add '-d invalid_mem' logging option (Zoltan)
 - Create QOM containers explicitly (Peter)
 - Rename sysemu/ -> system/ (Philippe)
 - Re-orderning of include/exec/ headers (Philippe)
   Move a lot of declarations from these legacy mixed bag headers:
     . "exec/cpu-all.h"
     . "exec/cpu-common.h"
     . "exec/cpu-defs.h"
     . "exec/exec-all.h"
     . "exec/translate-all"
   to these more specific ones:
     . "exec/page-protection.h"
     . "exec/translation-block.h"
     . "user/cpu_loop.h"
     . "user/guest-host.h"
     . "user/page-protection.h"
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Merge tag 'exec-20241220' of https://github.com/philmd/qemu into staging

Accel & Exec patch queue

- Ignore writes to CNTP_CTL_EL0 on HVF ARM (Alexander)
- Add '-d invalid_mem' logging option (Zoltan)
- Create QOM containers explicitly (Peter)
- Rename sysemu/ -> system/ (Philippe)
- Re-orderning of include/exec/ headers (Philippe)
  Move a lot of declarations from these legacy mixed bag headers:
    . "exec/cpu-all.h"
    . "exec/cpu-common.h"
    . "exec/cpu-defs.h"
    . "exec/exec-all.h"
    . "exec/translate-all"
  to these more specific ones:
    . "exec/page-protection.h"
    . "exec/translation-block.h"
    . "user/cpu_loop.h"
    . "user/guest-host.h"
    . "user/page-protection.h"

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 # gpg: Signature made Fri 20 Dec 2024 11:45:20 EST
 # gpg:                using RSA key FAABE75E12917221DCFD6BB2E3E32C2CDEADC0DE
 # gpg: Good signature from "Philippe Mathieu-Daudé (F4BUG) <f4bug@amsat.org>" [unknown]
 # gpg: WARNING: This key is not certified with a trusted signature!
 # gpg:          There is no indication that the signature belongs to the owner.
 # Primary key fingerprint: FAAB E75E 1291 7221 DCFD  6BB2 E3E3 2C2C DEAD C0DE

* tag 'exec-20241220' of https://github.com/philmd/qemu: (59 commits)
  util/qemu-timer: fix indentation
  meson: Do not define CONFIG_DEVICES on user emulation
  system/accel-ops: Remove unnecessary 'exec/cpu-common.h' header
  system/numa: Remove unnecessary 'exec/cpu-common.h' header
  hw/xen: Remove unnecessary 'exec/cpu-common.h' header
  target/mips: Drop left-over comment about Jazz machine
  target/mips: Remove tswap() calls in semihosting uhi_fstat_cb()
  target/xtensa: Remove tswap() calls in semihosting simcall() helper
  accel/tcg: Un-inline translator_is_same_page()
  accel/tcg: Include missing 'exec/translation-block.h' header
  accel/tcg: Move tcg_cflags_has/set() to 'exec/translation-block.h'
  accel/tcg: Restrict curr_cflags() declaration to 'internal-common.h'
  qemu/coroutine: Include missing 'qemu/atomic.h' header
  exec/translation-block: Include missing 'qemu/atomic.h' header
  accel/tcg: Declare cpu_loop_exit_requested() in 'exec/cpu-common.h'
  exec/cpu-all: Include 'cpu.h' earlier so MMU_USER_IDX is always defined
  target/sparc: Move sparc_restore_state_to_opc() to cpu.c
  target/sparc: Uninline cpu_get_tb_cpu_state()
  target/loongarch: Declare loongarch_cpu_dump_state() locally
  user: Move various declarations out of 'exec/exec-all.h'
  ...

Conflicts:
	hw/char/riscv_htif.c
	hw/intc/riscv_aplic.c
	target/s390x/cpu.c

	Apply sysemu header path changes to not in the pull request.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2024-12-21 11:07:00 -05:00
Philippe Mathieu-Daudé
32cad1ffb8 include: Rename sysemu/ -> system/
Headers in include/sysemu/ are not only related to system
*emulation*, they are also used by virtualization. Rename
as system/ which is clearer.

Files renamed manually then mechanical change using sed tool.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Lei Yang <leiyang@redhat.com>
Message-Id: <20241203172445.28576-1-philmd@linaro.org>
2024-12-20 17:44:56 +01:00
Fea.Wang
19eb69d09a target/riscv: Support hstatus[HUKTE] bit when svukte extension is enabled
Svukte extension add HUKTE bit, bit[24] in hstatus CSR. The written
value will be masked when the svukte extension is not enabled.

When hstatus[HUKTE] bit is set, HLV/HLVX/HSV work in the U-mode should
do svukte check.

Signed-off-by: Fea.Wang <fea.wang@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Jim Shu <jim.shu@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20241203034932.25185-4-fea.wang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-12-20 11:22:47 +10:00
Fea.Wang
81c8436277 target/riscv: Support senvcfg[UKTE] bit when svukte extension is enabled
Svukte extension add UKTE bit, bit[8] in senvcfg CSR. The bit will be
supported when the svukte extension is enabled.

When senvcfg[UKTE] bit is set, the memory access from U-mode should do
the svukte check only except HLV/HLVX/HSV H-mode instructions which
depend on hstatus[HUKTE].

Signed-off-by: Fea.Wang <fea.wang@sifive.com>
Reviewed-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Jim Shu <jim.shu@sifive.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20241203034932.25185-3-fea.wang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-12-20 11:22:47 +10:00
Deepak Gupta
8205bc127a target/riscv: introduce ssp and enabling controls for zicfiss
zicfiss introduces a new state ssp ("shadow stack register") in cpu.
ssp is expressed as a new unprivileged csr (CSR_SSP=0x11) and holds
virtual address for shadow stack as programmed by software.

Shadow stack (for each mode) is enabled via bit3 in *envcfg CSRs.
Shadow stack can be enabled for a mode only if it's higher privileged
mode had it enabled for itself. M mode doesn't need enabling control,
it's always available if extension is available on cpu.

This patch also implements helper bcfi function which determines if bcfi
is enabled at current privilege or not.

Adds ssp to migration state as well.

Signed-off-by: Deepak Gupta <debug@rivosinc.com>
Co-developed-by: Jim Shu <jim.shu@sifive.com>
Co-developed-by: Andy Chiu <andy.chiu@sifive.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20241008225010.1861630-12-debug@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-10-30 11:22:08 +10:00
Deepak Gupta
6031102401 target/riscv: additional code information for sw check
sw check exception support was recently added. This patch further augments
sw check exception by providing support for additional code which is
provided in *tval. Adds `sw_check_code` field in cpuarchstate. Whenever
sw check exception is raised *tval gets the value deposited in
`sw_check_code`.

Signed-off-by: Deepak Gupta <debug@rivosinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20241008225010.1861630-6-debug@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-10-30 11:22:08 +10:00
Deepak Gupta
4923f672e3 target/riscv: Introduce elp state and enabling controls for zicfilp
zicfilp introduces a new state elp ("expected landing pad") in cpu.
During normal execution, elp is idle (NO_LP_EXPECTED) i.e not expecting
landing pad. On an indirect call, elp moves LP_EXPECTED. When elp is
LP_EXPECTED, only a subsquent landing pad instruction can set state back
to NO_LP_EXPECTED. On reset, elp is set to NO_LP_EXPECTED.

zicfilp is enabled via bit2 in *envcfg CSRs. Enabling control for M-mode
is in mseccfg CSR at bit position 10.

On trap, elp state is saved away in *status.
Adds elp to the migration state as well.

Signed-off-by: Deepak Gupta <debug@rivosinc.com>
Co-developed-by: Jim Shu <jim.shu@sifive.com>
Co-developed-by: Andy Chiu <andy.chiu@sifive.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20241008225010.1861630-4-debug@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-10-30 11:22:08 +10:00
Evgenii Prokopiev
5a60026cad target/riscv/csr.c: Fix an access to VXSAT
The register VXSAT should be RW only to the first bit.
The remaining bits should be 0.

The RISC-V Instruction Set Manual Volume I: Unprivileged Architecture

The vxsat CSR has a single read-write least-significant bit (vxsat[0])
that indicates if a fixed-point instruction has had to saturate an output
value to fit into a destination format. Bits vxsat[XLEN-1:1]
should be written as zeros.

Signed-off-by: Evgenii Prokopiev <evgenii.prokopiev@syntacore.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20241002084436.89347-1-evgenii.prokopiev@syntacore.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-10-30 11:22:07 +10:00
Yu-Ming Chang
38c83e8d3a target/riscv: raise an exception when CSRRS/CSRRC writes a read-only CSR
Both CSRRS and CSRRC always read the addressed CSR and cause any read side
effects regardless of rs1 and rd fields. Note that if rs1 specifies a register
holding a zero value other than x0, the instruction will still attempt to write
the unmodified value back to the CSR and will cause any attendant side effects.

So if CSRRS or CSRRC tries to write a read-only CSR with rs1 which specifies
a register holding a zero value, an illegal instruction exception should be
raised.

Signed-off-by: Yu-Ming Chang <yumin686@andestech.com>
Signed-off-by: Alvin Chang <alvinga@andestech.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <172100444279.18077.6893072378718059541-0@git.sr.ht>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-07-18 12:08:45 +10:00
Rajnesh Kanwal
74112400df target/riscv: More accurately model priv mode filtering.
In case of programmable counters configured to count inst/cycles
we often end-up with counter not incrementing at all from kernel's
perspective.

For example:
- Kernel configures hpm3 to count instructions and sets hpmcounter
  to -10000 and all modes except U mode are inhibited.
- In QEMU we configure a timer to expire after ~10000 instructions.
- Problem is, it's often the case that kernel might not even schedule
  Umode task and we hit the timer callback in QEMU.
- In the timer callback we inject the interrupt into kernel, kernel
  runs the handler and reads hpmcounter3 value.
- Given QEMU maintains individual counters to count for each privilege
  mode, and given umode never ran, the umode counter didn't increment
  and QEMU returns same value as was programmed by the kernel when
  starting the counter.
- Kernel checks for overflow using previous and current value of the
  counter and reprograms the counter given there wasn't an overflow
  as per the counter value. (Which itself is a problem. We have QEMU
  telling kernel that counter3 overflowed but the counter value
  returned by QEMU doesn't seem to reflect that.).

This change makes sure that timer is reprogrammed from the handler
if the counter didn't overflow based on the counter value.

Second, this change makes sure that whenever the counter is read,
it's value is updated to reflect the latest count.

Signed-off-by: Rajnesh Kanwal <rkanwal@rivosinc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240711-smcntrpmf_v7-v8-11-b7c38ae7b263@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-07-18 12:08:45 +10:00
Rajnesh Kanwal
22c721c34c target/riscv: Start counters from both mhpmcounter and mcountinhibit
Currently we start timer counter from write_mhpmcounter path only
without checking for mcountinhibit bit. This changes adds mcountinhibit
check and also programs the counter from write_mcountinhibit as well.

When a counter is stopped using mcountinhibit we simply update
the value of the counter based on current host ticks and save
it for future reads.

We don't need to disable running timer as pmu_timer_trigger_irq
will discard the interrupt if the counter has been inhibited.

Signed-off-by: Rajnesh Kanwal <rkanwal@rivosinc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20240711-smcntrpmf_v7-v8-10-b7c38ae7b263@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2024-07-18 12:08:45 +10:00