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https://github.com/AsahiLinux/u-boot
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c63e137014
JEDEC spec requires the clocks to be stable before deasserting reset signal for RDIMMs. Clocks start when any chip select is enabled and clock control register is set. This patch also adds the interface to toggle memory reset signal if needed by the boards. Signed-off-by: York Sun <yorksun@freescale.com> |
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| .. | ||
| ddr.c | ||
| law.c | ||
| Makefile | ||
| p1_p2_rdb.c | ||
| pci.c | ||
| README | ||
| tlb.c | ||
Overview -------- P2020RDB is a Low End Dual core platform supporting the P2020 processor of QorIQ series. P2020 is an e500 based dual core SOC. Building U-boot ----------- To build the u-boot for P2020RDB: make P2020RDB_config make NOR Flash Banks ----------- RDB board for P2020 has two flash banks. They are both present on boot. Booting by default is always from the boot bank at 0xef00_0000. Memory Map ---------- 0xef00_0000 - 0xef7f_ffff Alternate bank 8MB 0xe800_0000 - 0xefff_ffff Boot bank 8MB 0xef78_0000 - 0xef7f_ffff Alternate u-boot address 512KB 0xeff8_0000 - 0xefff_ffff Boot u-boot address 512KB Switch settings to boot from the NOR flash banks ------------------------------------------------ SW4[8]=0 default NOR Flash bank SW4[8]=1 Alternate NOR Flash bank Flashing Images --------------- To place a new u-boot image in the alternate flash bank and then boot with that new image temporarily, use this: tftp 1000000 u-boot.bin erase ef780000 ef7fffff cp.b 1000000 ef780000 80000 Now to boot from the alternate bank change the SW4[8] from 0 to 1. To program the image in the boot flash bank: tftp 1000000 u-boot.bin protect off all erase eff80000 ffffffff cp.b 1000000 eff80000 80000 Using the Device Tree Source File --------------------------------- To create the DTB (Device Tree Binary) image file, use a command similar to this: dtc -b 0 -f -I dts -O dtb p2020rdb.dts > p2020rdb.dtb Likely, that .dts file will come from here; linux-2.6/arch/powerpc/boot/dts/p2020rdb.dts Booting Linux ------------- Place a linux uImage in the TFTP disk area. tftp 1000000 uImage.p2020rdb tftp 2000000 rootfs.ext2.gz.uboot tftp c00000 p2020rdb.dtb bootm 1000000 2000000 c00000 Implementing AMP(Asymmetric MultiProcessing) --------------------------------------------- 1. Build kernel image for core0: a. $ make 85xx/p1_p2_rdb_defconfig b. $ make menuconfig - un-select "Processor support"-> "Symetric multi-processing support" c. $ make uImage d. $ cp arch/powerpc/boot/uImage /tftpboot/uImage.core0 2. Build kernel image for core1: a. $ make 85xx/p1_p2_rdb_defconfig b. $ make menuconfig - Un-select "Processor support"-> "Symetric multi-processing support" - Select "Advanced setup" -> "Prompt for advanced kernel configuration options" - Select "Set physical address where the kernel is loaded" and set it to 0x20000000, assuming core1 will start from 512MB. - Select "Set custom page offset address" - Select "Set custom kernel base address" - Select "Set maximum low memory" - "Exit" and save the selection. c. $ make uImage d. $ cp arch/powerpc/boot/uImage /tftpboot/uImage.core1 3. Create dtb for core0: $ dtc -I dts -O dtb -f -b 0 arch/powerpc/boot/dts/p2020rdb_camp_core0.dts > /tftpboot/p2020rdb_camp_core0.dtb 4. Create dtb for core1: $ dtc -I dts -O dtb -f -b 1 arch/powerpc/boot/dts/p2020rdb_camp_core1.dts > /tftpboot/p2020rdb_camp_core1.dtb 5. Bring up two cores separately: a. Power on the board, under u-boot prompt: => setenv <serverip> => setenv <ipaddr> => setenv bootargs root=/dev/ram rw console=ttyS0,115200 b. Bring up core1's kernel first: => setenv bootm_low 0x20000000 => setenv bootm_size 0x10000000 => tftp 21000000 uImage.core1 => tftp 22000000 ramdiskfile => tftp 20c00000 p2020rdb_camp_core1.dtb => interrupts off => bootm start 21000000 22000000 20c00000 => bootm loados => bootm ramdisk => bootm fdt => fdt boardsetup => fdt chosen $initrd_start $initrd_end => bootm prep => cpu 1 release $bootm_low - $fdtaddr - c. Bring up core0's kernel(on the same u-boot console): => setenv bootm_low 0 => setenv bootm_size 0x20000000 => tftp 1000000 uImage.core0 => tftp 2000000 ramdiskfile => tftp c00000 p2020rdb_camp_core0.dtb => bootm 1000000 2000000 c00000 Please note only core0 will run u-boot, core1 starts kernel directly after "cpu release" command is issued.