diff options
Diffstat (limited to 'board')
-rw-r--r-- | board/freescale/mx50_rdp/flash_header.S | 83 |
1 files changed, 59 insertions, 24 deletions
diff --git a/board/freescale/mx50_rdp/flash_header.S b/board/freescale/mx50_rdp/flash_header.S index f6b01c8..3ba7fbf 100644 --- a/board/freescale/mx50_rdp/flash_header.S +++ b/board/freescale/mx50_rdp/flash_header.S @@ -300,32 +300,67 @@ plugin_start: str r1, [r0, #CLKCTL_CCSR] ldr r0, =PLL1_BASE_ADDR - ldr r1, =0x1232 - str r1, [r0, #PLL_DP_CTL] /* Set DPLL ON (set UPEN bit); BRMO=1 */ - ldr r1, =0x2 - str r1, [r0, #PLL_DP_CONFIG] /* Enable auto-restart AREN bit */ - - ldr r1, =DP_OP_800 - str r1, [r0, #PLL_DP_OP] - str r1, [r0, #PLL_DP_HFS_OP] - - ldr r1, =DP_MFD_800 - str r1, [r0, #PLL_DP_MFD] - str r1, [r0, #PLL_DP_HFS_MFD] - - ldr r1, =DP_MFN_800 - str r1, [r0, #PLL_DP_MFN] - str r1, [r0, #PLL_DP_HFS_MFN] - - /* Now restart PLL */ - ldr r1, =0x1232 - str r1, [r0, #PLL_DP_CTL] -wait_pll1_lock: - ldr r1, [r0, #PLL_DP_CTL] + + /* + * PLL1 workaround as the following + * (1) Disable AREN bit to avoid PLL1 restart during MFN change + * (2) set PLL1 to ~864Mhz with MFI = 8, MFN = 180, MFD = 179, PDF = 0 + * (3) Manual restart PLL1 + * (4) Wait PLL1 lock + * (5) Set PLL1 to 800Mhz with only change MFN to 60, others keep + * (6) Set LDREQ bit to load new MFN + * (7) Poll on LDREQ bit for MFN update to be completed + * (8) Delay at least 4 us to avoid PLL1 instability window + * (9) Switch ARM back to PLL1 + */ + /* Step 1 * / + ldr r1, [r0, #PLL_DP_CONFIG] + bic r1, r1, #0x2 + str r1, [r0, #PLL_DP_CONFIG] /* disable auto-restart AREN bit */ + + /* Step 2 */ + ldr r1, =0x80 + str r1, [r0, #PLL_DP_OP] + str r1, [r0, #PLL_DP_HFS_OP] + + ldr r1, =180 + str r1, [r0, #PLL_DP_MFN] + str r1, [r0, #PLL_DP_HFS_MFN] + + ldr r1, =179 + str r1, [r0, #PLL_DP_MFD] + str r1, [r0, #PLL_DP_HFS_MFD] + + /* Step 3. */ + ldr r1, =0x00001236 /* Set PLM =1, manual restart and enable PLL*/ + str r1, [r0, #PLL_DP_CTL] + + /* Step 4 */ +1: ldr r1, [r0, #0x0] ands r1, r1, #0x1 - beq wait_pll1_lock + beq 1b + + /* Step 5 - set PLL1 to 800Mhz */ + ldr r1, =60 + str r1, [r0, #PLL_DP_MFN] + str r1, [r0, #PLL_DP_HFS_MFN] + + /* Step 6 - Set the LDREQ bit */ + ldr r1, [r0, #PLL_DP_CONFIG] + orr r1, r1, #1 + str r1, [r0, #PLL_DP_CONFIG] + + /* Step 7 - Poll until LDREQ clears */ +2: ldr r1, [r0, #PLL_DP_CONFIG] + tst r1, #0x1 + bne 2b + + /* Step 8 - delay more than 4 us */ + mov r1, #100 +3: subs r1, r1, #1 + bge 3b -/* Switch ARM back to PLL1 */ + /* Step 9 - Switch ARM back to PLL1 */ ldr r0, =CCM_BASE_ADDR ldr r1, =0x0 str r1, [r0,#CLKCTL_CCSR] |