Hi, Neal:
Neal Liu <neal.liu@xxxxxxxxxxxx> 於 2020年6月15日 週一 上午10:43寫道：
>
> Hi Chun-Kuang,
>
>
> On Sun, 2020-06-14 at 11:26 +0800, Chun-Kuang Hu wrote:
> > Hi, Neal:
> >
> > Neal Liu <neal.liu@xxxxxxxxxxxx> 於 2020年6月9日 週二 下午6:25寫道：
> > >
> > > MT6873 bus frabric provides TrustZone security support and data
> > > protection to prevent slaves from being accessed by unexpected
> > > masters.
> > > The security violations are logged and sent to the processor for
> > > further analysis or countermeasures.
> > >
> > > Any occurrence of security violation would raise an interrupt, and
> > > it will be handled by devapc-mt6873 driver. The violation
> > > information is printed in order to find the murderer.
> > >
> > > Signed-off-by: Neal Liu <neal.liu@xxxxxxxxxxxx>
> > > ---
> >
> > [snip]
> >
> > > +
> > > + /* 50 */
> > > + {-1, -1, 50, "OOB_way_en", true},
> > > + {-1, -1, 51, "OOB_way_en", true},
> > > + {-1, -1, 52, "OOB_way_en", true},
> > > + {-1, -1, 53, "OOB_way_en", true},
> > > + {-1, -1, 54, "OOB_way_en", true},
> > > + {-1, -1, 55, "OOB_way_en", true},
> > > + {-1, -1, 56, "Decode_error", true},
> > > + {-1, -1, 57, "Decode_error", true},
> > > + {-1, -1, 58, "DISP_PWM", false},
> > > + {-1, -1, 59, "IMP_IIC_WRAP", false},
> > > +
> > > + /* 60 */
> > > + {-1, -1, 60, "DEVICE_APC_PERI_PAR__AO", false},
> > > + {-1, -1, 61, "DEVICE_APC_PERI_PAR_PDN", false},
> >
> > You does not process the item whose enable_vio_irq is false, so I
> > think you should remove these items and remove enable_vio_irq because
> > the rest item's enable_vio_irq would always be true.
>
> In some users, they can decide which slaves they want to enable or
> disable violation irq in different product. We remain this property for
> compatibility.
I think in upstream version, you could still remove enable_vio_irq and
process all items. For downstream case, users could remove items they
does not interest in.
>
> >
> > > +};
> > > +
> > > +static struct mtk_device_num mtk6873_devices_num[] = {
> > > + {SLAVE_TYPE_INFRA, VIO_SLAVE_NUM_INFRA},
> > > + {SLAVE_TYPE_PERI, VIO_SLAVE_NUM_PERI},
> > > + {SLAVE_TYPE_PERI2, VIO_SLAVE_NUM_PERI2},
> > > + {SLAVE_TYPE_PERI_PAR, VIO_SLAVE_NUM_PERI_PAR},
> > > +};
> > > +
> > > +static struct PERIAXI_ID_INFO peri_mi_id_to_master[] = {
> > > + {"THERM2", { 0, 0, 0 } },
> > > + {"SPM", { 0, 1, 0 } },
> > > + {"CCU", { 0, 0, 1 } },
> > > + {"THERM", { 0, 1, 1 } },
> > > + {"SPM_DRAMC", { 1, 1, 0 } },
> >
> > The bits { 1, 1, 0 } equal to a number 0x3, I thiink you should use a
> > number instead of bits and everything would be more easy.
>
> We would like to keep it because the bit value contains more than 0/1,
> it might be '2' in some cases. '2' means it can be 0 or 1. This totally
> by hardware design & implementation.
Upstream the patch that has dont-care-bits, otherwise, use a number for this.
Even there is dont-care-bits, I have a better way to process it. Here
is an example that has dont-care-bits:
+ {"Tinysys", { 0, 1, 0, 0, 2, 2, 2, 2, 2, 2, 0, 0, 0, 0 } },
I could use a { value, mask } pair for this case,
value = 0x0002; /* value for care bits */
mask = 0x3c02; /* mask for care bits */
So the compare statement would be
if ((bus_id & mask) == value)
So you could get rid of the second for-loop and reduce the processing
time in irq handler.
Regards,
Chun-Kuang.
