| Message ID | 20221212030804.927309-3-debug@rivosinc.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Support for zisslpcfi in opensbi | expand |
On Mon, Dec 12, 2022 at 11:10 AM Deepak Gupta <debug@rivosinc.com> wrote: > > This patch adds support for zsslpcfi detection in sbi_hart.c > If zsslpcfi is detected, this turns on menvcfg.CFI > > zsslpcfi records status of cfi state in xstatus csr. Missing landing pad > sets MPELP in mstatus. When SBI is redirecting back to S/VS/HS, SPELP is > set in sstatus/vsstatus. > > Signed-off-by: Deepak Gupta <debug@rivosinc.com> > --- > include/sbi/riscv_encoding.h | 2 ++ > lib/sbi/sbi_hart.c | 21 +++++++++++++++++++++ > lib/sbi/sbi_trap.c | 18 ++++++++++++++++++ > 3 files changed, 41 insertions(+) > > diff --git a/include/sbi/riscv_encoding.h b/include/sbi/riscv_encoding.h > index 1fb520f..d7886e7 100644 > --- a/include/sbi/riscv_encoding.h > +++ b/include/sbi/riscv_encoding.h > @@ -32,6 +32,8 @@ > #define MSTATUS_TVM _UL(0x00100000) > #define MSTATUS_TW _UL(0x00200000) > #define MSTATUS_TSR _UL(0x00400000) > +#define MSTATUS_SPELP _UL(0x10000000) > +#define MSTATUS_MPELP _UL(0x20000000) > #define MSTATUS32_SD _UL(0x80000000) > #if __riscv_xlen == 64 > #define MSTATUS_UXL _ULL(0x0000000300000000) > diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c > index 5447c52..6beae2d 100644 > --- a/lib/sbi/sbi_hart.c > +++ b/lib/sbi/sbi_hart.c > @@ -157,6 +157,16 @@ static void mstatus_init(struct sbi_scratch *scratch) > #endif > } > > + if (sbi_hart_has_extension(scratch, SBI_HART_EXT_SSLPCFI)) { > +#if __riscv_xlen == 32 > + unsigned long menvcfgh_val; > + menvcfgh_val = csr_read(CSR_MENVCFGH); > + menvcfgh_val |= ENVCFGH_CFI; > + csr_write(CSR_MENVCFGH, menvcfgh_val); > +#else > + menvcfg_val |= ENVCFG_CFI; > +#endif > + } > csr_write(CSR_MENVCFG, menvcfg_val); > } > > @@ -555,6 +565,7 @@ static int hart_detect_features(struct sbi_scratch *scratch) > sbi_scratch_offset_ptr(scratch, hart_features_offset); > unsigned long val, oldval; > int rc; > + int ssp_exist, lplr_exist; Use bool > > /* If hart features already detected then do nothing */ > if (hfeatures->detected) > @@ -693,6 +704,16 @@ __mhpm_skip: > SBI_HART_EXT_SMSTATEEN, true); > } > > + if (hfeatures->priv_version >= SBI_HART_PRIV_VER_1_12) { > + val = csr_read_allowed(CSR_SSP, (unsigned long)&trap); > + ssp_exist = trap.cause?0:1; need space around ? and : use true/false instead of 1/0 > + val = csr_read_allowed(CSR_LPLR, (unsigned long)&trap); > + lplr_exist = trap.cause?0:1; > + if (lplr_exist & ssp_exist) > + __sbi_hart_update_extension(hfeatures, > + SBI_HART_EXT_SSLPCFI, true); > + } > + > /* Let platform populate extensions */ > rc = sbi_platform_extensions_init(sbi_platform_thishart_ptr(), > hfeatures); > diff --git a/lib/sbi/sbi_trap.c b/lib/sbi/sbi_trap.c > index c875c90..a700041 100644 > --- a/lib/sbi/sbi_trap.c > +++ b/lib/sbi/sbi_trap.c > @@ -87,6 +87,7 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, > struct sbi_trap_info *trap) > { > ulong hstatus, vsstatus, prev_mode; > + bool elp = FALSE; s/FALSE/false > #if __riscv_xlen == 32 > bool prev_virt = (regs->mstatusH & MSTATUSH_MPV) ? TRUE : FALSE; > #else > @@ -100,6 +101,13 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, > if (prev_mode != PRV_S && prev_mode != PRV_U) > return SBI_ENOTSUPP; > > + /* If extension has support for CFI, clear MPELP because redirecting to VS or (H)S */ > + if (sbi_hart_has_extension(sbi_scratch_thishart_ptr(), SBI_HART_EXT_SSLPCFI)) { > + elp = (regs->mstatus & MSTATUS_MPELP)? TRUE: FALSE; > + /* Since redirecting, clear mpelp unconditionally */ > + regs->mstatus &= ~MSTATUS_MPELP; > + } > + > /* If exceptions came from VS/VU-mode, redirect to VS-mode if > * delegated in hedeleg > */ > @@ -153,6 +161,11 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, > /* Get VS-mode SSTATUS CSR */ > vsstatus = csr_read(CSR_VSSTATUS); > > + /*if elp was set, set it back in vsstatus */ need space after /* > + if (elp) { > + vsstatus |= MSTATUS_SPELP; > + } > + > /* Set SPP for VS-mode */ > vsstatus &= ~SSTATUS_SPP; > if (prev_mode == PRV_S) > @@ -193,6 +206,11 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, > > /* Clear SIE for S-mode */ > regs->mstatus &= ~MSTATUS_SIE; > + > + /* if elp was set, set it back in mstatus */ > + if (elp) { > + regs->mstatus |= MSTATUS_SPELP; > + } > } > Regards, Bin
On Dez 21 2022, Bin Meng wrote: >> @@ -693,6 +704,16 @@ __mhpm_skip: >> SBI_HART_EXT_SMSTATEEN, true); >> } >> >> + if (hfeatures->priv_version >= SBI_HART_PRIV_VER_1_12) { >> + val = csr_read_allowed(CSR_SSP, (unsigned long)&trap); >> + ssp_exist = trap.cause?0:1; ssp_exist = trap.cause == 0;
On Wed, Dec 21, 2022 at 5:43 AM Bin Meng <bmeng.cn@gmail.com> wrote: > > > @@ -87,6 +87,7 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, > > struct sbi_trap_info *trap) > > { > > ulong hstatus, vsstatus, prev_mode; > > + bool elp = FALSE; > > s/FALSE/false I followed whatever rest of the code is following. In the same function " int sbi_trap_redirect(struct sbi_trap_regs *regs, struct sbi_trap_info *trap) { ulong hstatus, vsstatus, prev_mode; bool elp = FALSE; #if __riscv_xlen == 32 bool prev_virt = (regs->mstatusH & MSTATUSH_MPV) ? TRUE : FALSE; #else bool prev_virt = (regs->mstatus & MSTATUS_MPV) ? TRUE : FALSE; #endif /* By default, we redirect to HS-mode */ bool next_virt = FALSE; " I can change it to false but it'll look ugly because at other places we're using upper case FALSE. Let me know what needs to be done. > > > #if __riscv_xlen == 32 > > bool prev_virt = (regs->mstatusH & MSTATUSH_MPV) ? TRUE : FALSE; > > #else > > @@ -100,6 +101,13 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, > > if (prev_mode != PRV_S && prev_mode != PRV_U) > > return SBI_ENOTSUPP; > > > > + /* If extension has support for CFI, clear MPELP because redirecting to VS or (H)S */ > > + if (sbi_hart_has_extension(sbi_scratch_thishart_ptr(), SBI_HART_EXT_SSLPCFI)) { > > + elp = (regs->mstatus & MSTATUS_MPELP)? TRUE: FALSE; > > + /* Since redirecting, clear mpelp unconditionally */ > > + regs->mstatus &= ~MSTATUS_MPELP; > > + } > > + > > /* If exceptions came from VS/VU-mode, redirect to VS-mode if > > * delegated in hedeleg > > */ > > @@ -153,6 +161,11 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, > > /* Get VS-mode SSTATUS CSR */ > > vsstatus = csr_read(CSR_VSSTATUS); > > > > + /*if elp was set, set it back in vsstatus */ > > need space after /* > > > + if (elp) { > > + vsstatus |= MSTATUS_SPELP; > > + } > > + > > /* Set SPP for VS-mode */ > > vsstatus &= ~SSTATUS_SPP; > > if (prev_mode == PRV_S) > > @@ -193,6 +206,11 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, > > > > /* Clear SIE for S-mode */ > > regs->mstatus &= ~MSTATUS_SIE; > > + > > + /* if elp was set, set it back in mstatus */ > > + if (elp) { > > + regs->mstatus |= MSTATUS_SPELP; > > + } > > } > > > > Regards, > Bin
Thanks Andreas and Bin for your review comments. Sent out v2 version of the patch. -Deepak On Wed, Dec 21, 2022 at 5:59 AM Andreas Schwab <schwab@suse.de> wrote: > > On Dez 21 2022, Bin Meng wrote: > > >> @@ -693,6 +704,16 @@ __mhpm_skip: > >> SBI_HART_EXT_SMSTATEEN, true); > >> } > >> > >> + if (hfeatures->priv_version >= SBI_HART_PRIV_VER_1_12) { > >> + val = csr_read_allowed(CSR_SSP, (unsigned long)&trap); > >> + ssp_exist = trap.cause?0:1; > > ssp_exist = trap.cause == 0; > > -- > Andreas Schwab, SUSE Labs, schwab@suse.de > GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7 > "And now for something completely different."
On Thu, Dec 22, 2022 at 2:41 AM Deepak Gupta <debug@rivosinc.com> wrote: > > On Wed, Dec 21, 2022 at 5:43 AM Bin Meng <bmeng.cn@gmail.com> wrote: > > > > > @@ -87,6 +87,7 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, > > > struct sbi_trap_info *trap) > > > { > > > ulong hstatus, vsstatus, prev_mode; > > > + bool elp = FALSE; > > > > s/FALSE/false > > I followed whatever rest of the code is following. In the same function > > " > int sbi_trap_redirect(struct sbi_trap_regs *regs, > struct sbi_trap_info *trap) > { > ulong hstatus, vsstatus, prev_mode; > bool elp = FALSE; > #if __riscv_xlen == 32 > bool prev_virt = (regs->mstatusH & MSTATUSH_MPV) ? TRUE : FALSE; > #else > bool prev_virt = (regs->mstatus & MSTATUS_MPV) ? TRUE : FALSE; > #endif > /* By default, we redirect to HS-mode */ > bool next_virt = FALSE; > " > I can change it to false but it'll look ugly because at other places > we're using upper case FALSE. > Let me know what needs to be done. > No need to worry about other places, as I already sent one patch to change all other places. Regards, Bin
diff --git a/include/sbi/riscv_encoding.h b/include/sbi/riscv_encoding.h index 1fb520f..d7886e7 100644 --- a/include/sbi/riscv_encoding.h +++ b/include/sbi/riscv_encoding.h @@ -32,6 +32,8 @@ #define MSTATUS_TVM _UL(0x00100000) #define MSTATUS_TW _UL(0x00200000) #define MSTATUS_TSR _UL(0x00400000) +#define MSTATUS_SPELP _UL(0x10000000) +#define MSTATUS_MPELP _UL(0x20000000) #define MSTATUS32_SD _UL(0x80000000) #if __riscv_xlen == 64 #define MSTATUS_UXL _ULL(0x0000000300000000) diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c index 5447c52..6beae2d 100644 --- a/lib/sbi/sbi_hart.c +++ b/lib/sbi/sbi_hart.c @@ -157,6 +157,16 @@ static void mstatus_init(struct sbi_scratch *scratch) #endif } + if (sbi_hart_has_extension(scratch, SBI_HART_EXT_SSLPCFI)) { +#if __riscv_xlen == 32 + unsigned long menvcfgh_val; + menvcfgh_val = csr_read(CSR_MENVCFGH); + menvcfgh_val |= ENVCFGH_CFI; + csr_write(CSR_MENVCFGH, menvcfgh_val); +#else + menvcfg_val |= ENVCFG_CFI; +#endif + } csr_write(CSR_MENVCFG, menvcfg_val); } @@ -555,6 +565,7 @@ static int hart_detect_features(struct sbi_scratch *scratch) sbi_scratch_offset_ptr(scratch, hart_features_offset); unsigned long val, oldval; int rc; + int ssp_exist, lplr_exist; /* If hart features already detected then do nothing */ if (hfeatures->detected) @@ -693,6 +704,16 @@ __mhpm_skip: SBI_HART_EXT_SMSTATEEN, true); } + if (hfeatures->priv_version >= SBI_HART_PRIV_VER_1_12) { + val = csr_read_allowed(CSR_SSP, (unsigned long)&trap); + ssp_exist = trap.cause?0:1; + val = csr_read_allowed(CSR_LPLR, (unsigned long)&trap); + lplr_exist = trap.cause?0:1; + if (lplr_exist & ssp_exist) + __sbi_hart_update_extension(hfeatures, + SBI_HART_EXT_SSLPCFI, true); + } + /* Let platform populate extensions */ rc = sbi_platform_extensions_init(sbi_platform_thishart_ptr(), hfeatures); diff --git a/lib/sbi/sbi_trap.c b/lib/sbi/sbi_trap.c index c875c90..a700041 100644 --- a/lib/sbi/sbi_trap.c +++ b/lib/sbi/sbi_trap.c @@ -87,6 +87,7 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, struct sbi_trap_info *trap) { ulong hstatus, vsstatus, prev_mode; + bool elp = FALSE; #if __riscv_xlen == 32 bool prev_virt = (regs->mstatusH & MSTATUSH_MPV) ? TRUE : FALSE; #else @@ -100,6 +101,13 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, if (prev_mode != PRV_S && prev_mode != PRV_U) return SBI_ENOTSUPP; + /* If extension has support for CFI, clear MPELP because redirecting to VS or (H)S */ + if (sbi_hart_has_extension(sbi_scratch_thishart_ptr(), SBI_HART_EXT_SSLPCFI)) { + elp = (regs->mstatus & MSTATUS_MPELP)? TRUE: FALSE; + /* Since redirecting, clear mpelp unconditionally */ + regs->mstatus &= ~MSTATUS_MPELP; + } + /* If exceptions came from VS/VU-mode, redirect to VS-mode if * delegated in hedeleg */ @@ -153,6 +161,11 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, /* Get VS-mode SSTATUS CSR */ vsstatus = csr_read(CSR_VSSTATUS); + /*if elp was set, set it back in vsstatus */ + if (elp) { + vsstatus |= MSTATUS_SPELP; + } + /* Set SPP for VS-mode */ vsstatus &= ~SSTATUS_SPP; if (prev_mode == PRV_S) @@ -193,6 +206,11 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, /* Clear SIE for S-mode */ regs->mstatus &= ~MSTATUS_SIE; + + /* if elp was set, set it back in mstatus */ + if (elp) { + regs->mstatus |= MSTATUS_SPELP; + } } return 0;
This patch adds support for zsslpcfi detection in sbi_hart.c If zsslpcfi is detected, this turns on menvcfg.CFI zsslpcfi records status of cfi state in xstatus csr. Missing landing pad sets MPELP in mstatus. When SBI is redirecting back to S/VS/HS, SPELP is set in sstatus/vsstatus. Signed-off-by: Deepak Gupta <debug@rivosinc.com> --- include/sbi/riscv_encoding.h | 2 ++ lib/sbi/sbi_hart.c | 21 +++++++++++++++++++++ lib/sbi/sbi_trap.c | 18 ++++++++++++++++++ 3 files changed, 41 insertions(+)