diff options
Diffstat (limited to 'board/xsengine/lowlevel_init.S')
| -rw-r--r-- | board/xsengine/lowlevel_init.S | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/board/xsengine/lowlevel_init.S b/board/xsengine/lowlevel_init.S new file mode 100644 index 0000000..309faab --- /dev/null +++ b/board/xsengine/lowlevel_init.S @@ -0,0 +1,221 @@ +#include <config.h> +#include <version.h> +#include <asm/arch/pxa-regs.h> + +DRAM_SIZE: .long CFG_DRAM_SIZE + +.globl lowlevel_init +lowlevel_init: + + mov r10, lr + +/* ---- GPIO INITIALISATION ---- */ +/* Set up GPIO pins first (3 groups [31:0] [63:32] [80:64]) */ + + /* General purpose set registers */ + ldr r0, =GPSR0 + ldr r1, =CFG_GPSR0_VAL + str r1, [r0] + ldr r0, =GPSR1 + ldr r1, =CFG_GPSR1_VAL + str r1, [r0] + ldr r0, =GPSR2 + ldr r1, =CFG_GPSR2_VAL + str r1, [r0] + + /* General purpose clear registers */ + ldr r0, =GPCR0 + ldr r1, =CFG_GPCR0_VAL + str r1, [r0] + ldr r0, =GPCR1 + ldr r1, =CFG_GPCR1_VAL + str r1, [r0] + ldr r0, =GPCR2 + ldr r1, =CFG_GPCR2_VAL + str r1, [r0] + + /* General rising edge registers */ + ldr r0, =GRER0 + ldr r1, =CFG_GRER0_VAL + str r1, [r0] + ldr r0, =GRER1 + ldr r1, =CFG_GRER1_VAL + str r1, [r0] + ldr r0, =GRER2 + ldr r1, =CFG_GRER2_VAL + str r1, [r0] + + /* General falling edge registers */ + ldr r0, =GFER0 + ldr r1, =CFG_GFER0_VAL + str r1, [r0] + ldr r0, =GFER1 + ldr r1, =CFG_GFER1_VAL + str r1, [r0] + ldr r0, =GFER2 + ldr r1, =CFG_GFER2_VAL + str r1, [r0] + + /* General edge detect registers */ + ldr r0, =GPDR0 + ldr r1, =CFG_GPDR0_VAL + str r1, [r0] + ldr r0, =GPDR1 + ldr r1, =CFG_GPDR1_VAL + str r1, [r0] + ldr r0, =GPDR2 + ldr r1, =CFG_GPDR2_VAL + str r1, [r0] + + /* General alternate function registers */ + ldr r0, =GAFR0_L /* [0:15] */ + ldr r1, =CFG_GAFR0_L_VAL + str r1, [r0] + ldr r0, =GAFR0_U /* [31:16] */ + ldr r1, =CFG_GAFR0_U_VAL + str r1, [r0] + ldr r0, =GAFR1_L /* [47:32] */ + ldr r1, =CFG_GAFR1_L_VAL + str r1, [r0] + ldr r0, =GAFR1_U /* [63:48] */ + ldr r1, =CFG_GAFR1_U_VAL + str r1, [r0] + ldr r0, =GAFR2_L /* [79:64] */ + ldr r1, =CFG_GAFR2_L_VAL + str r1, [r0] + ldr r0, =GAFR2_U /* [80] */ + ldr r1, =CFG_GAFR2_U_VAL + str r1, [r0] + + /* General purpose direction registers */ + ldr r0, =GPDR0 + ldr r1, =CFG_GPDR0_VAL + str r1, [r0] + ldr r0, =GPDR1 + ldr r1, =CFG_GPDR1_VAL + str r1, [r0] + ldr r0, =GPDR2 + ldr r1, =CFG_GPDR2_VAL + str r1, [r0] + + /* Power manager sleep status */ + ldr r0, =PSSR + ldr r1, =CFG_PSSR_VAL + str r1, [r0] + +/* ---- MEMORY INITIALISATION ---- */ +/* Initialize Memory Controller, see PXA250 Operating System Developer's Guide */ +/* pause for 200 uSecs- allow internal clocks to settle */ + ldr r3, =OSCR /* reset the OS Timer Count to zero */ + mov r2, #0 + str r2, [r3] + ldr r4, =0x300 /* really 0x2E1 is about 200usec, so 0x300 should be plenty */ +1: + ldr r2, [r3] + cmp r4, r2 + bgt 1b + +mem_init: +/* get memory controller base address */ + ldr r1, =MEMC_BASE + +/* ---- FLASH INITIALISATION ---- */ +/* Write MSC0 and read back to ensure data change is accepted by cpu */ + ldr r2, =CFG_MSC0_VAL + str r2, [r1, #MSC0_OFFSET] + ldr r2, [r1, #MSC0_OFFSET] + +/* ---- SDRAM INITIALISATION ---- */ +/* get the MDREFR settings */ + ldr r2, =CFG_MDREFR_VAL + str r2, [r1, #MDREFR_OFFSET] + +/* fetch platform value of MDCNFG */ + ldr r2, =CFG_MDCNFG_VAL + +/* disable all sdram banks */ + bic r2, r2, #(MDCNFG_DE0 | MDCNFG_DE1) + bic r2, r2, #(MDCNFG_DE2 | MDCNFG_DE3) + +/* write initial value of MDCNFG, w/o enabling sdram banks */ + str r2, [r1, #MDCNFG_OFFSET] + +/* pause for 200 uSecs */ + ldr r3, =OSCR /* reset the OS Timer Count to zero */ + mov r2, #0 + str r2, [r3] + ldr r4, =0x300 /* about 200 usec */ +1: + ldr r2, [r3] + cmp r4, r2 + bgt 1b + +/* Access memory *not yet enabled* for CBR refresh cycles (8) */ +/* CBR is generated for all banks */ + + ldr r2, =CFG_DRAM_BASE + str r2, [r2] + str r2, [r2] + str r2, [r2] + str r2, [r2] + str r2, [r2] + str r2, [r2] + str r2, [r2] + str r2, [r2] + +/* get memory controller base address */ + ldr r2, =MEMC_BASE + +/* Enable SDRAM bank 0 in MDCNFG register */ + ldr r2, [r1, #MDCNFG_OFFSET] + orr r2, r2, #MDCNFG_DE0 + str r2, [r1, #MDCNFG_OFFSET] + +/* write MDMRS to trigger an MSR command to all enabled SDRAM banks */ + ldr r2, =CFG_MDMRS_VAL + str r2, [r1, #MDMRS_OFFSET] + +/* ---- INTERRUPT INITIALISATION ---- */ +/* Disable (mask) all interrupts at the interrupt controller */ +/* clear the interrupt level register (use IRQ, not FIQ) */ + mov r1, #0 + ldr r2, =ICLR + str r1, [r2] + +/* Set interrupt mask register */ + ldr r1, =CFG_ICMR_VAL + ldr r2, =ICMR + str r1, [r2] + +/* ---- CLOCK INITIALISATION ---- */ +/* Disable the peripheral clocks, and set the core clock */ + +/* Turn Off ALL on-chip peripheral clocks for re-configuration */ + ldr r1, =CKEN + mov r2, #0 + str r2, [r1] + +/* set core clocks */ + ldr r2, =CFG_CCCR_VAL + ldr r1, =CCCR + str r2, [r1] + +#ifdef ENABLE32KHZ +/* enable the 32Khz oscillator for RTC and PowerManager */ + ldr r1, =OSCC + mov r2, #OSCC_OON + str r2, [r1] + +/* NOTE: spin here until OSCC.OOK get set, meaning the PLL has settled. */ +60: + ldr r2, [r1] + ands r2, r2, #1 + beq 60b +#endif + +/* Turn on needed clocks */ + ldr r1, =CKEN + ldr r2, =CFG_CKEN_VAL + str r2, [r1] + + mov pc, r10 |