diff options
Diffstat (limited to 'sys/dev/sio/sio.c')
| -rw-r--r-- | sys/dev/sio/sio.c | 42 |
1 files changed, 19 insertions, 23 deletions
diff --git a/sys/dev/sio/sio.c b/sys/dev/sio/sio.c index 61bbfdc..2a3d8ac 100644 --- a/sys/dev/sio/sio.c +++ b/sys/dev/sio/sio.c @@ -120,7 +120,7 @@ #define COM_C_IIR_TXRDYBUG (0x80000) #define COM_IIR_TXRDYBUG(flags) ((flags) & COM_C_IIR_TXRDYBUG) #define COM_NOSCR(flags) ((flags) & 0x100000) -#define COM_TI16754(flags) ((flags) & 0x200000) +#define COM_TI16754(flags) ((flags) & 0x200000) #define COM_FIFOSIZE(flags) (((flags) & 0xff000000) >> 24) #define sio_getreg(com, off) \ @@ -606,32 +606,28 @@ sioprobe(dev, xrid, rclk, noprobe) /* EXTRA DELAY? */ /* - * For the TI16754 chips set prescaler to 1 (4 is often the - * default after-reset value), otherwise it's impossible to + * For the TI16754 chips, set prescaler to 1 (4 is often the + * default after-reset value) as otherwise it's impossible to * get highest baudrates. */ if (COM_TI16754(flags)) { - u_char t1, t2; - - /* Save LCR */ - t1 = sio_getreg(com, com_lctl); - /* Enable EFR */ - sio_setreg(com, com_lctl, 0xbf); - /* Save EFR */ - t2 = sio_getreg(com, com_iir); - /* Unlock MCR[7] */ - sio_setreg(com, com_iir, t2 | 0x10); - /* Disable EFR */ - sio_setreg(com, com_lctl, 0); - /* Set prescaler to 1 */ - sio_setreg(com, com_mcr, sio_getreg(com, com_mcr) & 0x7f); - /* Enable EFR */ - sio_setreg(com, com_lctl, 0xbf); - /* Restore EFR */ - sio_setreg(com, com_iir, t2); - /* Restore LCR */ - sio_setreg(com, com_lctl, t1); + u_char cfcr, efr; + + cfcr = sio_getreg(com, com_cfcr); + sio_setreg(com, com_cfcr, CFCR_EFR_ENABLE); + efr = sio_getreg(com, com_efr); + /* Unlock extended features to turn off prescaler. */ + sio_setreg(com, com_efr, efr | EFR_EFE); + /* Disable EFR. */ + sio_setreg(com, com_cfcr, (cfcr != CFCR_EFR_ENABLE) ? cfcr : 0); + /* Turn off prescaler. */ + sio_setreg(com, com_mcr, + sio_getreg(com, com_mcr) & ~MCR_PRESCALE); + sio_setreg(com, com_cfcr, CFCR_EFR_ENABLE); + sio_setreg(com, com_efr, efr); + sio_setreg(com, com_cfcr, cfcr); } + /* * Initialize the speed and the word size and wait long enough to * drain the maximum of 16 bytes of junk in device output queues. |
