Message ID | 20230914-nmi-i2c-v6-1-11bbb4f74d18@samsung.com |
---|---|
State | New |
Headers | show |
Series | hw/{i2c,nvme}: mctp endpoint, nvme management interface model | expand |
On Thu, Sep 14, 2023 at 11:53:41AM +0200, Klaus Jensen wrote: > From: Klaus Jensen <k.jensen@samsung.com> > > Add i2c_smbus_pec() to calculate the SMBus Packet Error Code for a > message. Seems fine. Acked-by: Corey Minyard <cminyard@mvista.com> > > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > Signed-off-by: Klaus Jensen <k.jensen@samsung.com> > --- > hw/i2c/smbus_master.c | 26 ++++++++++++++++++++++++++ > include/hw/i2c/smbus_master.h | 2 ++ > 2 files changed, 28 insertions(+) > > diff --git a/hw/i2c/smbus_master.c b/hw/i2c/smbus_master.c > index 6a53c34e70b7..01a8e4700222 100644 > --- a/hw/i2c/smbus_master.c > +++ b/hw/i2c/smbus_master.c > @@ -15,6 +15,32 @@ > #include "hw/i2c/i2c.h" > #include "hw/i2c/smbus_master.h" > > +static uint8_t crc8(uint16_t data) > +{ > + int i; > + > + for (i = 0; i < 8; i++) { > + if (data & 0x8000) { > + data ^= 0x1070U << 3; > + } > + > + data <<= 1; > + } > + > + return (uint8_t)(data >> 8); > +} > + > +uint8_t i2c_smbus_pec(uint8_t crc, uint8_t *buf, size_t len) > +{ > + int i; > + > + for (i = 0; i < len; i++) { > + crc = crc8((crc ^ buf[i]) << 8); > + } > + > + return crc; > +} > + > /* Master device commands. */ > int smbus_quick_command(I2CBus *bus, uint8_t addr, int read) > { > diff --git a/include/hw/i2c/smbus_master.h b/include/hw/i2c/smbus_master.h > index bb13bc423c22..d90f81767d86 100644 > --- a/include/hw/i2c/smbus_master.h > +++ b/include/hw/i2c/smbus_master.h > @@ -27,6 +27,8 @@ > > #include "hw/i2c/i2c.h" > > +uint8_t i2c_smbus_pec(uint8_t crc, uint8_t *buf, size_t len); > + > /* Master device commands. */ > int smbus_quick_command(I2CBus *bus, uint8_t addr, int read); > int smbus_receive_byte(I2CBus *bus, uint8_t addr); > > -- > 2.42.0 > >
On Thu, 2023-09-14 at 11:53 +0200, Klaus Jensen wrote: > From: Klaus Jensen <k.jensen@samsung.com> > > Add i2c_smbus_pec() to calculate the SMBus Packet Error Code for a > message. > > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > Signed-off-by: Klaus Jensen <k.jensen@samsung.com> It at least looks a lot like the linux implementation :) Reviewed-by: Andrew Jeffery <andrew@codeconstruct.com.au> > --- > hw/i2c/smbus_master.c | 26 ++++++++++++++++++++++++++ > include/hw/i2c/smbus_master.h | 2 ++ > 2 files changed, 28 insertions(+) > > diff --git a/hw/i2c/smbus_master.c b/hw/i2c/smbus_master.c > index 6a53c34e70b7..01a8e4700222 100644 > --- a/hw/i2c/smbus_master.c > +++ b/hw/i2c/smbus_master.c > @@ -15,6 +15,32 @@ > #include "hw/i2c/i2c.h" > #include "hw/i2c/smbus_master.h" > > +static uint8_t crc8(uint16_t data) > +{ > + int i; > + > + for (i = 0; i < 8; i++) { > + if (data & 0x8000) { > + data ^= 0x1070U << 3; > + } > + > + data <<= 1; > + } > + > + return (uint8_t)(data >> 8); > +} > + > +uint8_t i2c_smbus_pec(uint8_t crc, uint8_t *buf, size_t len) > +{ > + int i; > + > + for (i = 0; i < len; i++) { > + crc = crc8((crc ^ buf[i]) << 8); > + } > + > + return crc; > +} > + > /* Master device commands. */ > int smbus_quick_command(I2CBus *bus, uint8_t addr, int read) > { > diff --git a/include/hw/i2c/smbus_master.h b/include/hw/i2c/smbus_master.h > index bb13bc423c22..d90f81767d86 100644 > --- a/include/hw/i2c/smbus_master.h > +++ b/include/hw/i2c/smbus_master.h > @@ -27,6 +27,8 @@ > > #include "hw/i2c/i2c.h" > > +uint8_t i2c_smbus_pec(uint8_t crc, uint8_t *buf, size_t len); > + > /* Master device commands. */ > int smbus_quick_command(I2CBus *bus, uint8_t addr, int read); > int smbus_receive_byte(I2CBus *bus, uint8_t addr); >
diff --git a/hw/i2c/smbus_master.c b/hw/i2c/smbus_master.c index 6a53c34e70b7..01a8e4700222 100644 --- a/hw/i2c/smbus_master.c +++ b/hw/i2c/smbus_master.c @@ -15,6 +15,32 @@ #include "hw/i2c/i2c.h" #include "hw/i2c/smbus_master.h" +static uint8_t crc8(uint16_t data) +{ + int i; + + for (i = 0; i < 8; i++) { + if (data & 0x8000) { + data ^= 0x1070U << 3; + } + + data <<= 1; + } + + return (uint8_t)(data >> 8); +} + +uint8_t i2c_smbus_pec(uint8_t crc, uint8_t *buf, size_t len) +{ + int i; + + for (i = 0; i < len; i++) { + crc = crc8((crc ^ buf[i]) << 8); + } + + return crc; +} + /* Master device commands. */ int smbus_quick_command(I2CBus *bus, uint8_t addr, int read) { diff --git a/include/hw/i2c/smbus_master.h b/include/hw/i2c/smbus_master.h index bb13bc423c22..d90f81767d86 100644 --- a/include/hw/i2c/smbus_master.h +++ b/include/hw/i2c/smbus_master.h @@ -27,6 +27,8 @@ #include "hw/i2c/i2c.h" +uint8_t i2c_smbus_pec(uint8_t crc, uint8_t *buf, size_t len); + /* Master device commands. */ int smbus_quick_command(I2CBus *bus, uint8_t addr, int read); int smbus_receive_byte(I2CBus *bus, uint8_t addr);