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-rw-r--r--cpu/ppc4xx/start.S177
1 files changed, 175 insertions, 2 deletions
diff --git a/cpu/ppc4xx/start.S b/cpu/ppc4xx/start.S
index c334f936b39..afe8635585c 100644
--- a/cpu/ppc4xx/start.S
+++ b/cpu/ppc4xx/start.S
@@ -297,7 +297,7 @@ _start_440:
mflr r1
mtspr srr0,r1
rfi
-#endif
+#endif /* CONFIG_440 */
/*
* r3 - 1st arg to board_init(): IMMP pointer
@@ -504,7 +504,7 @@ _start:
#endif /* CONFIG_IOP480 */
/*****************************************************************************/
-#if defined(CONFIG_405GP) || defined(CONFIG_405CR) || defined(CONFIG_405)
+#if defined(CONFIG_405GP) || defined(CONFIG_405CR) || defined(CONFIG_405) || defined(CONFIG_405EP)
/*----------------------------------------------------------------------- */
/* Clear and set up some registers. */
/*----------------------------------------------------------------------- */
@@ -551,6 +551,17 @@ _start:
bl ext_bus_cntlr_init
#endif
+#if defined(CONFIG_405EP)
+ /*----------------------------------------------------------------------- */
+ /* DMA Status, clear to come up clean */
+ /*----------------------------------------------------------------------- */
+ addis r3,r0, 0xFFFF /* Clear all existing DMA status */
+ ori r3,r3, 0xFFFF
+ mtdcr dmasr, r3
+
+ bl ppc405ep_init /* do ppc405ep specific init */
+#endif /* CONFIG_405EP */
+
#if defined(CFG_OCM_DATA_ADDR) && defined(CFG_OCM_DATA_SIZE)
/********************************************************************
* Setup OCM - On Chip Memory
@@ -693,6 +704,7 @@ _start:
#endif /* CONFIG_405GP || CONFIG_405CR */
+/*****************************************************************************/
.globl _start_of_vectors
_start_of_vectors:
@@ -1437,3 +1449,164 @@ trap_reloc:
stw r0, 4(r7)
blr
+
+
+/**************************************************************************/
+/* PPC405EP specific stuff */
+/**************************************************************************/
+#ifdef CONFIG_405EP
+ppc405ep_init:
+ /*
+ !-----------------------------------------------------------------------
+ ! Check FPGA for PCI internal/external arbitration
+ ! If board is set to internal arbitration, update cpc0_pci
+ !-----------------------------------------------------------------------
+ */
+ addi r3,0,CPC0_PCI_HOST_CFG_EN
+#ifdef CONFIG_BUBINGA405EP
+ addis r5,r0,FPGA_REG1@h /* set offset for FPGA_REG1 */
+ ori r5,r5,FPGA_REG1@l
+ lbz r5,0x0(r5) /* read to get PCI arb selection */
+ andi. r6,r5,FPGA_REG1_PCI_INT_ARB /* using internal arbiter ?*/
+ beq ..pci_cfg_set /* if not set, then bypass reg write*/
+#endif
+ ori r3,r3,CPC0_PCI_ARBIT_EN
+..pci_cfg_set:
+ mtdcr CPC0_PCI, r3 /* Enable internal arbiter*/
+
+ /*
+ !-----------------------------------------------------------------------
+ ! Check to see if chip is in bypass mode.
+ ! If so, write stored CPC0_PLLMR0 and CPC0_PLLMR1 values and perform a
+ ! CPU reset Otherwise, skip this step and keep going.
+ ! Note: Running BIOS in bypass mode is not supported since PLB speed
+ ! will not be fast enough for the SDRAM (min 66MHz)
+ !-----------------------------------------------------------------------
+ */
+ mfdcr r5, CPC0_PLLMR1
+ rlwinm r4,r5,1,0x1 /* get system clock source (SSCS) */
+ cmpi cr0,0,r4,0x1
+
+ beq pll_done /* if SSCS =b'1' then PLL has */
+ /* already been set */
+ /* and CPU has been reset */
+ /* so skip to next section */
+
+#ifdef CONFIG_BUBINGA405EP
+ /*
+ !-----------------------------------------------------------------------
+ ! Read NVRAM to get value to write in PLLMR.
+ ! If value has not been correctly saved, write default value
+ ! Default config values (assuming on-board 33MHz SYS_CLK) are above.
+ ! See CPU_DEFAULT_200 and CPU_DEFAULT_266 above.
+ !
+ ! WARNING: This code assumes the first three words in the nvram_t
+ ! structure in openbios.h. Changing the beginning of
+ ! the structure will break this code.
+ !
+ !-----------------------------------------------------------------------
+ */
+ addis r3,0,NVRAM_BASE@h
+ addi r3,r3,NVRAM_BASE@l
+
+ lwz r4, 0(r3)
+ addis r5,0,NVRVFY1@h
+ addi r5,r5,NVRVFY1@l
+ cmp cr0,0,r4,r5 /* Compare 1st NVRAM Magic number*/
+ bne ..no_pllset
+ addi r3,r3,4
+ lwz r4, 0(r3)
+ addis r5,0,NVRVFY2@h
+ addi r5,r5,NVRVFY2@l
+ cmp cr0,0,r4,r5 /* Compare 2 NVRAM Magic number */
+ bne ..no_pllset
+ addi r3,r3,8 /* Skip over conf_size */
+ lwz r4, 4(r3) /* Load PLLMR1 value from NVRAM */
+ lwz r3, 0(r3) /* Load PLLMR0 value from NVRAM */
+ rlwinm r5,r4,1,0x1 /* get system clock source (SSCS) */
+ cmpi cr0,0,r5,1 /* See if PLL is locked */
+ beq pll_write
+..no_pllset:
+#endif /* CONFIG_BUBINGA405EP */
+
+ addis r3,0,PLLMR0_DEFAULT@h /* PLLMR0 default value */
+ ori r3,r3,PLLMR0_DEFAULT@l /* */
+ addis r4,0,PLLMR1_DEFAULT@h /* PLLMR1 default value */
+ ori r4,r4,PLLMR1_DEFAULT@l /* */
+
+ b pll_write /* Write the CPC0_PLLMR with new value */
+
+pll_done:
+ /*
+ !-----------------------------------------------------------------------
+ ! Clear Soft Reset Register
+ ! This is needed to enable PCI if not booting from serial EPROM
+ !-----------------------------------------------------------------------
+ */
+ addi r3, 0, 0x0
+ mtdcr CPC0_SRR, r3
+
+ addis r3,0,0x0010
+ mtctr r3
+pci_wait:
+ bdnz pci_wait
+
+ blr /* return to main code */
+
+/*
+!-----------------------------------------------------------------------------
+! Function: pll_write
+! Description: Updates the value of the CPC0_PLLMR according to CMOS27E documentation
+! That is:
+! 1. Pll is first disabled (de-activated by putting in bypass mode)
+! 2. PLL is reset
+! 3. Clock dividers are set while PLL is held in reset and bypassed
+! 4. PLL Reset is cleared
+! 5. Wait 100us for PLL to lock
+! 6. A core reset is performed
+! Input: r3 = Value to write to CPC0_PLLMR0
+! Input: r4 = Value to write to CPC0_PLLMR1
+! Output r3 = none
+!-----------------------------------------------------------------------------
+*/
+pll_write:
+ mfdcr r5, CPC0_UCR
+ andis. r5,r5,0xFFFF
+ ori r5,r5,0x0101 /* Stop the UART clocks */
+ mtdcr CPC0_UCR,r5 /* Before changing PLL */
+
+ mfdcr r5, CPC0_PLLMR1
+ rlwinm r5,r5,0,0x7FFFFFFF /* Disable PLL */
+ mtdcr CPC0_PLLMR1,r5
+ oris r5,r5,0x4000 /* Set PLL Reset */
+ mtdcr CPC0_PLLMR1,r5
+
+ mtdcr CPC0_PLLMR0,r3 /* Set clock dividers */
+ rlwinm r5,r4,0,0x3FFFFFFF /* Reset & Bypass new PLL dividers */
+ oris r5,r5,0x4000 /* Set PLL Reset */
+ mtdcr CPC0_PLLMR1,r5 /* Set clock dividers */
+ rlwinm r5,r5,0,0xBFFFFFFF /* Clear PLL Reset */
+ mtdcr CPC0_PLLMR1,r5
+
+ /*
+ ! Wait min of 100us for PLL to lock.
+ ! See CMOS 27E databook for more info.
+ ! At 200MHz, that means waiting 20,000 instructions
+ */
+ addi r3,0,20000 /* 2000 = 0x4e20 */
+ mtctr r3
+pll_wait:
+ bdnz pll_wait
+
+ oris r5,r5,0x8000 /* Enable PLL */
+ mtdcr CPC0_PLLMR1,r5 /* Engage */
+
+ /*
+ * Reset CPU to guarantee timings are OK
+ * Not sure if this is needed...
+ */
+ addis r3,0,0x1000
+ mtspr dbcr0,r3 /* This will cause a CPU core reset, and */
+ /* execution will continue from the poweron */
+ /* vector of 0xfffffffc */
+#endif /* CONFIG_405EP */