X-Git-Url: http://git.ipfire.org/?p=people%2Fms%2Fu-boot.git;a=blobdiff_plain;f=README;h=fabd532623924bbdf1a32d471b8862e5e5c2e36c;hp=242287ca9b930c6a33a8bd9b523b8b48d22da856;hb=20fa1dd386c891f7d6477e7d442dda76af6c765b;hpb=002e91087c817f8281fccee327e0d8e98c691a2f diff --git a/README b/README index 242287ca9b..fabd532623 100644 --- a/README +++ b/README @@ -143,6 +143,7 @@ Directory Hierarchy: /nios2 Files generic to Altera NIOS2 architecture /openrisc Files generic to OpenRISC architecture /powerpc Files generic to PowerPC architecture + /riscv Files generic to RISC-V architecture /sandbox Files generic to HW-independent "sandbox" /sh Files generic to SH architecture /x86 Files generic to x86 architecture @@ -713,11 +714,6 @@ The following options need to be configured: RAM and NFS. - Bootcount: - CONFIG_BOOTCOUNT_LIMIT - Implements a mechanism for detecting a repeating reboot - cycle, see: - http://www.denx.de/wiki/view/DULG/UBootBootCountLimit - CONFIG_BOOTCOUNT_ENV If no softreset save registers are found on the hardware "bootcount" is stored in the environment. To prevent a @@ -1028,21 +1024,6 @@ The following options need to be configured: control registers. This behavior won't affect the correctnessof 10/100 link speed update. - CONFIG_SMC911X - Support for SMSC's LAN911x and LAN921x chips - - CONFIG_SMC911X_BASE - Define this to hold the physical address - of the device (I/O space) - - CONFIG_SMC911X_32_BIT - Define this if data bus is 32 bits - - CONFIG_SMC911X_16_BIT - Define this if data bus is 16 bits. If your processor - automatically converts one 32 bit word to two 16 bit - words you may also try CONFIG_SMC911X_32_BIT. - CONFIG_SH_ETHER Support for Renesas on-chip Ethernet controller @@ -1618,6 +1599,15 @@ The following options need to be configured: See doc/README.link-local for more information. + - MAC address from environment variables + + FDT_SEQ_MACADDR_FROM_ENV + + Fix-up device tree with MAC addresses fetched sequentially from + environment variables. This config work on assumption that + non-usable ethernet node of device-tree are either not present + or their status has been marked as "disabled". + - CDP Options: CONFIG_CDP_DEVICE_ID @@ -2006,11 +1996,6 @@ The following options need to be configured: SPI EEPROM, also an instance works with Crystal A/D and D/As on the SACSng board) - CONFIG_SH_SPI - - Enables the driver for SPI controller on SuperH. Currently - only SH7757 is supported. - CONFIG_SOFT_SPI Enables a software (bit-bang) SPI driver rather than @@ -2029,11 +2014,6 @@ The following options need to be configured: Currently supported on some MPC8xxx processors. For an example, see include/configs/mpc8349emds.h. - CONFIG_MXC_SPI - - Enables the driver for the SPI controllers on i.MX and MXC - SoCs. Currently i.MX31/35/51 are supported. - CONFIG_SYS_SPI_MXC_WAIT Timeout for waiting until spi transfer completed. default: (CONFIG_SYS_HZ/100) /* 10 ms */ @@ -2183,16 +2163,6 @@ The following options need to be configured: currently only supports clearing the memory. - Error Recovery: - CONFIG_PANIC_HANG - - Define this variable to stop the system in case of a - fatal error, so that you have to reset it manually. - This is probably NOT a good idea for an embedded - system where you want the system to reboot - automatically as fast as possible, but it may be - useful during development since you can try to debug - the conditions that lead to the situation. - CONFIG_NET_RETRY_COUNT This variable defines the number of retries for @@ -2326,18 +2296,6 @@ The following options need to be configured: CONFIG_SF_DEFAULT_MODE (see include/spi.h) CONFIG_SF_DEFAULT_SPEED in Hz - CONFIG_SYSTEMACE - - Adding this option adds support for Xilinx SystemACE - chips attached via some sort of local bus. The address - of the chip must also be defined in the - CONFIG_SYS_SYSTEMACE_BASE macro. For example: - - #define CONFIG_SYSTEMACE - #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 - - When SystemACE support is added, the "ace" device type - becomes available to the fat commands, i.e. fatls. - TFTP Fixed UDP Port: CONFIG_TFTP_PORT @@ -2360,11 +2318,6 @@ The following options need to be configured: but sometimes that is not allowed. - bootcount support: - CONFIG_BOOTCOUNT_LIMIT - - This enables the bootcounter support, see: - http://www.denx.de/wiki/DULG/UBootBootCountLimit - CONFIG_AT91SAM9XE enable special bootcounter support on at91sam9xe based boards. CONFIG_SOC_DA8XX @@ -2377,6 +2330,13 @@ The following options need to be configured: CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for the bootcounter. CONFIG_BOOTCOUNT_ALEN = address len + CONFIG_BOOTCOUNT_EXT + enable support for the bootcounter in EXT filesystem + CONFIG_SYS_BOOTCOUNT_ADDR = RAM address used for read + and write. + CONFIG_SYS_BOOTCOUNT_EXT_INTERFACE = interface + CONFIG_SYS_BOOTCOUNT_EXT_DEVPART = device and part + CONFIG_SYS_BOOTCOUNT_EXT_NAME = filename - Show boot progress: CONFIG_SHOW_BOOT_PROGRESS @@ -2734,11 +2694,6 @@ FIT uImage format: CONFIG_SYS_SPL_MALLOC_SIZE The size of the malloc pool used in SPL. - CONFIG_SPL_FRAMEWORK - Enable the SPL framework under common/. This framework - supports MMC, NAND and YMODEM loading of U-Boot and NAND - NAND loading of the Linux Kernel. - CONFIG_SPL_OS_BOOT Enable booting directly to an OS from SPL. See also: doc/README.falcon @@ -3519,7 +3474,7 @@ Low Level (hardware related) configuration options: globally (CONFIG_CMD_MEMORY). - CONFIG_SKIP_LOWLEVEL_INIT - [ARM, NDS32, MIPS only] If this variable is defined, then certain + [ARM, NDS32, MIPS, RISC-V only] If this variable is defined, then certain low level initializations (like setting up the memory controller) are omitted and/or U-Boot does not relocate itself into RAM. @@ -3727,6 +3682,11 @@ this behavior and build U-Boot to some external directory: Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment variable. +User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by +setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS. +For example to treat all compiler warnings as errors: + + make KCFLAGS=-Werror Please be aware that the Makefiles assume you are using GNU make, so for instance on NetBSD you might need to use "gmake" instead of @@ -4973,6 +4933,22 @@ On NDS32, the following registers are used: NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, or current versions of GCC may "optimize" the code too much. +On RISC-V, the following registers are used: + + x0: hard-wired zero (zero) + x1: return address (ra) + x2: stack pointer (sp) + x3: global pointer (gp) + x4: thread pointer (tp) + x5: link register (t0) + x8: frame pointer (fp) + x10-x11: arguments/return values (a0-1) + x12-x17: arguments (a2-7) + x28-31: temporaries (t3-6) + pc: program counter (pc) + + ==> U-Boot will use gp to hold a pointer to the global data + Memory Management: ------------------ @@ -5134,8 +5110,9 @@ Coding Standards: ----------------- All contributions to U-Boot should conform to the Linux kernel -coding style; see the file "Documentation/CodingStyle" and the script -"scripts/Lindent" in your Linux kernel source directory. +coding style; see the kernel coding style guide at +https://www.kernel.org/doc/html/latest/process/coding-style.html, and the +script "scripts/Lindent" in your Linux kernel source directory. Source files originating from a different project (for example the MTD subsystem) are generally exempt from these guidelines and are not @@ -5167,7 +5144,7 @@ may be rejected, even when they contain important and valuable stuff. Please see http://www.denx.de/wiki/U-Boot/Patches for details. Patches shall be sent to the u-boot mailing list ; -see http://lists.denx.de/mailman/listinfo/u-boot +see https://lists.denx.de/listinfo/u-boot When you send a patch, please include the following information with it: