diff options
| author | henryk <henryk@6dc7ffe9-61d6-0310-9af1-9938baff3ed1> | 2007-11-29 20:38:00 +0000 |
|---|---|---|
| committer | henryk <henryk@6dc7ffe9-61d6-0310-9af1-9938baff3ed1> | 2007-11-29 20:38:00 +0000 |
| commit | 3d2ce8df12898dbdb0b545340fe536b470c7a998 (patch) | |
| tree | aa0c323453b2283a1614b1f23debb9f9f909d951 /openpicc/os | |
| parent | 5b7a3102608e452474775d204257b1b522b819cf (diff) | |
Fix SSC TX registers (especially the clock source selection), peripheral configuration in ssc_tx_init
Implement software (FIQ based) workaround for the problem that TF seemingly cannot be used as a start condition
git-svn-id: https://svn.openpcd.org:2342/trunk@360 6dc7ffe9-61d6-0310-9af1-9938baff3ed1
Diffstat (limited to 'openpicc/os')
| -rw-r--r-- | openpicc/os/boot/boot.s | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/openpicc/os/boot/boot.s b/openpicc/os/boot/boot.s index cedd3ee..43c4885 100644 --- a/openpicc/os/boot/boot.s +++ b/openpicc/os/boot/boot.s @@ -4,6 +4,7 @@ .extern exit .extern AT91F_LowLevelInit .extern pio_irq_isr_value + .extern ssc_tx_pending .text .code 32 @@ -45,10 +46,13 @@ .equ AT91C_BASE_PIOA, 0xFFFFF400 .equ AT91C_BASE_TC0, 0xFFFA0000 .equ AT91C_BASE_SSC, 0xFFFD4000 +.equ SSC_CR, 0x0 .equ SSC_RCMR, 0x10 +.equ SSC_CR_TXEN, 0x100 .equ AT91C_TC_SWTRG, (1 << 2) .equ AT91C_TC_CLKEN, (1 << 0) .equ PIO_DATA, (1 << 27) +.equ PIO_SSC_TF, (1 << 15) .equ PIOA_SODR, 0x30 .equ PIOA_CODR, 0x34 .equ PIOA_PDSR, 0x3c @@ -219,6 +223,26 @@ my_fiq_handler: movne r11, #PIO_DATA strne r11, [r10, #PIOA_IDR] /* disable further PIO_DATA FIQ */ + tst r8, #PIO_SSC_TF /* check for SSC Transmit Frame signal */ + ldrne r11, [r10, #PIOA_PDSR] + tstne r11, #PIO_SSC_TF /* check for SSC_TF == 1 */ + + movne r11, #PIO_SSC_TF + strne r11, [r10, #PIOA_IDR] /* disable further SSC_TF FIQ */ + + ldrne r11, =ssc_tx_pending + ldrne r8, [r11] + tstne r8, #0x01 /* Check whether a TX is pending */ + + beq .no_ssc + mov r8, #0x00 + str r8, [r11] /* Set ssc_tx_pending to 0 */ + + ldr r11, =AT91C_BASE_SSC + mov r8, #SSC_CR_TXEN + str r8, [r11, #SSC_CR] /* Write TXEN to SSC_CR, enables tx */ + +.no_ssc: /* Trigger PIO_SECONDARY_IRQ */ mov r11, #PIO_SECONDARY_IRQ_BIT ldr r8, =AT91C_BASE_AIC |