| Message ID | 1510170356-16953-1-git-send-email-stefanb@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 11/08/2017 02:45 PM, Stefan Berger wrote: > Add a caching layer for the TPM established flag so that we don't > need to go to the backend every time the flag is read by accessing > the REG_ACCESS register. The v2 I just sent moves this to the tpm_emulator. Stefan > > Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> > --- > hw/tpm/tpm_tis.c | 27 +++++++++++++++++++++++++-- > 1 file changed, 25 insertions(+), 2 deletions(-) > > diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c > index 7402528..6b81bbf 100644 > --- a/hw/tpm/tpm_tis.c > +++ b/hw/tpm/tpm_tis.c > @@ -95,6 +95,9 @@ struct TPMState { > char *backend; > TPMBackend *be_driver; > TPMVersion be_tpm_version; > + > + unsigned int established_flag:1; > + unsigned int established_flag_cached:1; > }; > > #define TPM(obj) OBJECT_CHECK(TPMState, (obj), TYPE_TPM_TIS) > @@ -529,6 +532,26 @@ static void tpm_tis_dump_state(void *opaque, hwaddr addr) > } > #endif > > +static void tpm_tis_reset_tpm_established_flag(TPMState *s, > + uint8_t locty) > +{ > + s->established_flag_cached = 0; > + > + tpm_backend_reset_tpm_established_flag(s->be_driver, locty); > +} > + > +static unsigned int tpm_tis_get_tpm_established_flag(TPMState *s) > +{ > + if (s->established_flag_cached) { > + return s->established_flag; > + } > + > + s->established_flag = !tpm_backend_get_tpm_established_flag(s->be_driver); > + s->established_flag_cached = 1; > + > + return s->established_flag; > +} > + > /* > * Read a register of the TIS interface > * See specs pages 33-63 for description of the registers > @@ -556,7 +579,7 @@ static uint64_t tpm_tis_mmio_read(void *opaque, hwaddr addr, > if (tpm_tis_check_request_use_except(s, locty)) { > val |= TPM_TIS_ACCESS_PENDING_REQUEST; > } > - val |= !tpm_backend_get_tpm_established_flag(s->be_driver); > + val |= tpm_tis_get_tpm_established_flag(s); > break; > case TPM_TIS_REG_INT_ENABLE: > val = s->loc[locty].inte; > @@ -840,7 +863,7 @@ static void tpm_tis_mmio_write(void *opaque, hwaddr addr, > > if (val & TPM_TIS_STS_RESET_ESTABLISHMENT_BIT) { > if (locty == 3 || locty == 4) { > - tpm_backend_reset_tpm_established_flag(s->be_driver, locty); > + tpm_tis_reset_tpm_established_flag(s, locty); > } > } > }
diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c index 7402528..6b81bbf 100644 --- a/hw/tpm/tpm_tis.c +++ b/hw/tpm/tpm_tis.c @@ -95,6 +95,9 @@ struct TPMState { char *backend; TPMBackend *be_driver; TPMVersion be_tpm_version; + + unsigned int established_flag:1; + unsigned int established_flag_cached:1; }; #define TPM(obj) OBJECT_CHECK(TPMState, (obj), TYPE_TPM_TIS) @@ -529,6 +532,26 @@ static void tpm_tis_dump_state(void *opaque, hwaddr addr) } #endif +static void tpm_tis_reset_tpm_established_flag(TPMState *s, + uint8_t locty) +{ + s->established_flag_cached = 0; + + tpm_backend_reset_tpm_established_flag(s->be_driver, locty); +} + +static unsigned int tpm_tis_get_tpm_established_flag(TPMState *s) +{ + if (s->established_flag_cached) { + return s->established_flag; + } + + s->established_flag = !tpm_backend_get_tpm_established_flag(s->be_driver); + s->established_flag_cached = 1; + + return s->established_flag; +} + /* * Read a register of the TIS interface * See specs pages 33-63 for description of the registers @@ -556,7 +579,7 @@ static uint64_t tpm_tis_mmio_read(void *opaque, hwaddr addr, if (tpm_tis_check_request_use_except(s, locty)) { val |= TPM_TIS_ACCESS_PENDING_REQUEST; } - val |= !tpm_backend_get_tpm_established_flag(s->be_driver); + val |= tpm_tis_get_tpm_established_flag(s); break; case TPM_TIS_REG_INT_ENABLE: val = s->loc[locty].inte; @@ -840,7 +863,7 @@ static void tpm_tis_mmio_write(void *opaque, hwaddr addr, if (val & TPM_TIS_STS_RESET_ESTABLISHMENT_BIT) { if (locty == 3 || locty == 4) { - tpm_backend_reset_tpm_established_flag(s->be_driver, locty); + tpm_tis_reset_tpm_established_flag(s, locty); } } }
Add a caching layer for the TPM established flag so that we don't need to go to the backend every time the flag is read by accessing the REG_ACCESS register. Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> --- hw/tpm/tpm_tis.c | 27 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-)