| Message ID | 20161209093158.3161-4-jglauber@cavium.com |
|---|---|
| State | Accepted |
| Headers | show |
On Fri, Dec 09, 2016 at 10:31:57AM +0100, Jan Glauber wrote: > Do not infinitely retry register readq and writeq operations > in order to not lock up the CPU in case the TWSI gets stuck. > > Return -EIO in case of a failed data read. For all other > cases just return so subsequent operations will fail > and trigger the recovery. > > Signed-off-by: Jan Glauber <jglauber@cavium.com> I can't apply this one?
On Sun, Dec 11, 2016 at 11:01:48PM +0100, Wolfram Sang wrote: > On Fri, Dec 09, 2016 at 10:31:57AM +0100, Jan Glauber wrote: > > Do not infinitely retry register readq and writeq operations > > in order to not lock up the CPU in case the TWSI gets stuck. > > > > Return -EIO in case of a failed data read. For all other > > cases just return so subsequent operations will fail > > and trigger the recovery. > > > > Signed-off-by: Jan Glauber <jglauber@cavium.com> > > I can't apply this one? > Strange. Applies for me on top of 4.9 and also next-20161212. I can also apply if back from the mail. Is the mail messed up on your side? -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
> > > > I can't apply this one? > > > > Strange. Applies for me on top of 4.9 and also next-20161212. > I can also apply if back from the mail. Is the mail messed up on your > side? My fault, sorry for the noise. My branch missed the latest revert for 4.9. I'll apply this patch for a second pull request during the merge window.
On Fri, Dec 09, 2016 at 10:31:57AM +0100, Jan Glauber wrote: > Do not infinitely retry register readq and writeq operations > in order to not lock up the CPU in case the TWSI gets stuck. > > Return -EIO in case of a failed data read. For all other > cases just return so subsequent operations will fail > and trigger the recovery. > > Signed-off-by: Jan Glauber <jglauber@cavium.com> Applied to for-current, thanks!
diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c index 3d10f1a..1d8775799 100644 --- a/drivers/i2c/busses/i2c-octeon-core.c +++ b/drivers/i2c/busses/i2c-octeon-core.c @@ -342,7 +342,9 @@ static int octeon_i2c_read(struct octeon_i2c *i2c, int target, if (result) return result; - data[i] = octeon_i2c_data_read(i2c); + data[i] = octeon_i2c_data_read(i2c, &result); + if (result) + return result; if (recv_len && i == 0) { if (data[i] > I2C_SMBUS_BLOCK_MAX + 1) return -EPROTO; diff --git a/drivers/i2c/busses/i2c-octeon-core.h b/drivers/i2c/busses/i2c-octeon-core.h index 87151ea..e160f83 100644 --- a/drivers/i2c/busses/i2c-octeon-core.h +++ b/drivers/i2c/busses/i2c-octeon-core.h @@ -141,11 +141,14 @@ static inline void octeon_i2c_writeq_flush(u64 val, void __iomem *addr) */ static inline void octeon_i2c_reg_write(struct octeon_i2c *i2c, u64 eop_reg, u8 data) { + int tries = 1000; u64 tmp; __raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + SW_TWSI(i2c)); do { tmp = __raw_readq(i2c->twsi_base + SW_TWSI(i2c)); + if (--tries < 0) + return; } while ((tmp & SW_TWSI_V) != 0); } @@ -163,24 +166,32 @@ static inline void octeon_i2c_reg_write(struct octeon_i2c *i2c, u64 eop_reg, u8 * * The I2C core registers are accessed indirectly via the SW_TWSI CSR. */ -static inline u8 octeon_i2c_reg_read(struct octeon_i2c *i2c, u64 eop_reg) +static inline int octeon_i2c_reg_read(struct octeon_i2c *i2c, u64 eop_reg, + int *error) { + int tries = 1000; u64 tmp; __raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base + SW_TWSI(i2c)); do { tmp = __raw_readq(i2c->twsi_base + SW_TWSI(i2c)); + if (--tries < 0) { + /* signal that the returned data is invalid */ + if (error) + *error = -EIO; + return 0; + } } while ((tmp & SW_TWSI_V) != 0); return tmp & 0xFF; } #define octeon_i2c_ctl_read(i2c) \ - octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_CTL) -#define octeon_i2c_data_read(i2c) \ - octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_DATA) + octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_CTL, NULL) +#define octeon_i2c_data_read(i2c, error) \ + octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_DATA, error) #define octeon_i2c_stat_read(i2c) \ - octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_STAT) + octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_STAT, NULL) /** * octeon_i2c_read_int - read the TWSI_INT register
Do not infinitely retry register readq and writeq operations in order to not lock up the CPU in case the TWSI gets stuck. Return -EIO in case of a failed data read. For all other cases just return so subsequent operations will fail and trigger the recovery. Signed-off-by: Jan Glauber <jglauber@cavium.com> --- drivers/i2c/busses/i2c-octeon-core.c | 4 +++- drivers/i2c/busses/i2c-octeon-core.h | 21 ++++++++++++++++----- 2 files changed, 19 insertions(+), 6 deletions(-)