diff options
| -rw-r--r-- | README | 54 | ||||
| -rw-r--r-- | common/cmd_bootm.c | 40 |
2 files changed, 80 insertions, 14 deletions
@@ -447,6 +447,11 @@ The following options need to be configured: Board code has addition modification that it wants to make to the flat device tree before handing it off to the kernel + CONFIG_OF_BOOT_CPU + + This define fills in the correct boot cpu in the boot + param header, the default value is zero if undefined. + - Serial Ports: CFG_PL010_SERIAL @@ -3013,6 +3018,55 @@ format!) to the "bootm" command: bash# +Boot Linux and pass a flat device tree: +----------- + +First, U-Boot must be compiled with the appropriate defines. See the section +titled "Linux Kernel Interface" above for a more in depth explanation. The +following is an example of how to start a kernel and pass an updated +flat device tree: + +=> print oftaddr +oftaddr=0x300000 +=> print oft +oft=oftrees/mpc8540ads.dtb +=> tftp $oftaddr $oft +Speed: 1000, full duplex +Using TSEC0 device +TFTP from server 192.168.1.1; our IP address is 192.168.1.101 +Filename 'oftrees/mpc8540ads.dtb'. +Load address: 0x300000 +Loading: # +done +Bytes transferred = 4106 (100a hex) +=> tftp $loadaddr $bootfile +Speed: 1000, full duplex +Using TSEC0 device +TFTP from server 192.168.1.1; our IP address is 192.168.1.2 +Filename 'uImage'. +Load address: 0x200000 +Loading:############ +done +Bytes transferred = 1029407 (fb51f hex) +=> print loadaddr +loadaddr=200000 +=> print oftaddr +oftaddr=0x300000 +=> bootm $loadaddr - $oftaddr +## Booting image at 00200000 ... + Image Name: Linux-2.6.17-dirty + Image Type: PowerPC Linux Kernel Image (gzip compressed) + Data Size: 1029343 Bytes = 1005.2 kB + Load Address: 00000000 + Entry Point: 00000000 + Verifying Checksum ... OK + Uncompressing Kernel Image ... OK +Booting using flat device tree at 0x300000 +Using MPC85xx ADS machine description +Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb +[snip] + + More About U-Boot Image Types: ------------------------------ diff --git a/common/cmd_bootm.c b/common/cmd_bootm.c index fdf7180..a472a1d 100644 --- a/common/cmd_bootm.c +++ b/common/cmd_bootm.c @@ -465,6 +465,13 @@ U_BOOT_CMD( "[addr [arg ...]]\n - boot application image stored in memory\n" "\tpassing arguments 'arg ...'; when booting a Linux kernel,\n" "\t'arg' can be the address of an initrd image\n" +#ifdef CONFIG_OF_FLAT_TREE + "\tWhen booting a Linux kernel which requires a flat device-tree\n" + "\ta third argument is required which is the address of the of the\n" + "\tdevice-tree blob. To boot that kernel without an initrd image,\n" + "\tuse a '-' for the second argument. If you do not pass a third\n" + "\ta bd_info struct will be passed instead\n" +#endif ); #ifdef CONFIG_SILENT_CONSOLE @@ -500,11 +507,6 @@ fixup_silent_linux () } #endif /* CONFIG_SILENT_CONSOLE */ -#ifdef CONFIG_OF_FLAT_TREE -extern const unsigned char oftree_dtb[]; -extern const unsigned int oftree_dtb_len; -#endif - #ifdef CONFIG_PPC static void do_bootm_linux (cmd_tbl_t *cmdtp, int flag, @@ -616,7 +618,17 @@ do_bootm_linux (cmd_tbl_t *cmdtp, int flag, /* * Check if there is an initrd image */ + +#ifdef CONFIG_OF_FLAT_TREE + /* Look for a '-' which indicates to ignore the ramdisk argument */ + if (argc >= 3 && strcmp(argv[2], "-") == 0) { + debug ("Skipping initrd\n"); + data = 0; + } + else +#endif if (argc >= 3) { + debug ("Not skipping initrd\n"); SHOW_BOOT_PROGRESS (9); addr = simple_strtoul(argv[2], NULL, 16); @@ -724,6 +736,15 @@ do_bootm_linux (cmd_tbl_t *cmdtp, int flag, len = data = 0; } +#ifdef CONFIG_OF_FLAT_TREE + if (argc >= 3) + { + of_flat_tree = (char *) simple_strtoul(argv[3], NULL, 16); + printf ("Booting using flat device tree at 0x%x\n", + of_flat_tree); + } +#endif + if (!data) { debug ("No initrd\n"); } @@ -793,15 +814,6 @@ do_bootm_linux (cmd_tbl_t *cmdtp, int flag, initrd_end = 0; } -#ifdef CONFIG_OF_FLAT_TREE - if (initrd_start == 0) - of_flat_tree = (char *)(((ulong)kbd - OF_FLAT_TREE_MAX_SIZE - - sizeof(bd_t)) & ~0xF); - else - of_flat_tree = (char *)((initrd_start - OF_FLAT_TREE_MAX_SIZE - - sizeof(bd_t)) & ~0xF); -#endif - debug ("## Transferring control to Linux (at address %08lx) ...\n", (ulong)kernel); |