diff options
Diffstat (limited to 'cf-code/cf-fsi-fw.S')
| -rw-r--r-- | cf-code/cf-fsi-fw.S | 50 |
1 files changed, 44 insertions, 6 deletions
diff --git a/cf-code/cf-fsi-fw.S b/cf-code/cf-fsi-fw.S index a68ce68..533cf39 100644 --- a/cf-code/cf-fsi-fw.S +++ b/cf-code/cf-fsi-fw.S @@ -200,21 +200,56 @@ _start: move.b #FW_VERSION,%a1@(FW_VERS_REG) move.b #API_VERSION,%a1@(API_VERS_REG) + /* Clear arbitration register */ + move.b #0,%a1@(ARB_REG) + /* * Main command loop */ main_loop: lea %a1@(TRACEBUF),%a3 - /* Wait for command */ -1: move.l %a1@(CMD_REG),%d2 + /* Wait arbitration request or command + * + * Note: This can run with interrupts enabled as a result of + * the stop op, so %d0 can be clobbered at any time. + */ +1: move.b %a1@(ARB_REG),%d2 + bne arbitration_request + move.l %a1@(CMD_REG),%d2 tst.b %d2 - bne 1f + bne command_request stop #0x2000 bra 1b +arbitration_request: /* Mask interrupts */ -1: move.w #0x2007,%sr + move.w #0x2007,%sr + + /* Ack request */ + move.b #ARB_ARM_ACK,%a1@(ARB_REG) + + /* Wait until it's cleared by the host */ +0: move.b %a1@(ARB_REG),%d1 + bne 1f + + /* Got it, re-load the GPIO caches */ + move.l %a5@(0),%DCLK + move.l %a4@(0),%DDAT + + /* Reconfigure data as output just in case ... */ + bsr config_gpio_out + + /* Back to main loop */ + bra main_loop + + /* Wait, we'll get an interrupt when the host clears it */ +1: stop #0x2000 + bra 0b + +command_request: + /* Mask interrupts */ + move.w #0x2007,%sr /* Mark ourselves as sending a command */ move.b #STAT_SENDING,%a1@(STAT_REG) @@ -443,10 +478,13 @@ config_gpio_in: move.l %d0,%a4@(4) rts - /* Interrupt handler */ + /* Interrupt handler + * + * Note: Must only clobber %d0 + */ _int: addq.l #1,%a1@(INT_CNT) - moveq.l #CVIC_SW_IRQ, %d0 + moveq.l #CVIC_SW_IRQ,%d0 move.l %d0,%a2@(CVIC_SW_IRQ_CLR) rte |
