Merge branch 'master' of git://git.denx.de/u-boot-sunxi

[u-boot] / README

diff --git a/README b/README
index 242287ca9b930c6a33a8bd9b523b8b48d22da856..b1ddf89fc588290a85311c713260df3718e1c86e 100644 (file)
--- a/README
+++ b/README
@@ -1,9 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0+

 #
 # (C) Copyright 2000 - 2013
 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 #
 # (C) Copyright 2000 - 2013
 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.

-#
-# SPDX-License-Identifier:     GPL-2.0+
-#

 
 Summary:
 ========
 
 Summary:
 ========


@@ -143,6 +141,7 @@ Directory Hierarchy:
   /nios2               Files generic to Altera NIOS2 architecture
   /openrisc            Files generic to OpenRISC architecture
   /powerpc             Files generic to PowerPC architecture
   /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
   /sandbox             Files generic to HW-independent "sandbox"
   /sh                  Files generic to SH architecture
   /x86                 Files generic to x86 architecture


@@ -332,11 +331,6 @@ The following options need to be configured:
 
 - Board Type:  Define exactly one, e.g. CONFIG_MPC8540ADS.
 
 
 - Board Type:  Define exactly one, e.g. CONFIG_MPC8540ADS.
 

-- Marvell Family Member
-               CONFIG_SYS_MVFS         - define it if you want to enable
-                                         multiple fs option at one time
-                                         for marvell soc family
-

 - 85xx CPU Options:
                CONFIG_SYS_PPC64
 
 - 85xx CPU Options:
                CONFIG_SYS_PPC64
 


@@ -712,22 +706,6 @@ The following options need to be configured:
                as a convenience, when switching between booting from
                RAM and NFS.
 
                as a convenience, when switching between booting from
                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
-               saveenv on all reboots, the environment variable
-               "upgrade_available" is used. If "upgrade_available" is
-               0, "bootcount" is always 0, if "upgrade_available" is
-               1 "bootcount" is incremented in the environment.
-               So the Userspace Applikation must set the "upgrade_available"
-               and "bootcount" variable to 0, if a boot was successfully.
-

 - Pre-Boot Commands:
                CONFIG_PREBOOT
 
 - Pre-Boot Commands:
                CONFIG_PREBOOT
 


@@ -827,14 +805,6 @@ The following options need to be configured:
                CONFIG_AT91_HW_WDT_TIMEOUT
                specify the timeout in seconds. default 2 seconds.
 
                CONFIG_AT91_HW_WDT_TIMEOUT
                specify the timeout in seconds. default 2 seconds.
 

-- U-Boot Version:
-               CONFIG_VERSION_VARIABLE
-               If this variable is defined, an environment variable
-               named "ver" is created by U-Boot showing the U-Boot
-               version as printed by the "version" command.
-               Any change to this variable will be reverted at the
-               next reset.
-

 - Real-Time Clock:
 
                When CONFIG_CMD_DATE is selected, the type of the RTC
 - Real-Time Clock:
 
                When CONFIG_CMD_DATE is selected, the type of the RTC


@@ -1028,21 +998,6 @@ The following options need to be configured:
                        control registers. This behavior won't affect the
                        correctnessof 10/100 link speed update.
 
                        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
 
                CONFIG_SH_ETHER
                Support for Renesas on-chip Ethernet controller
 


@@ -1212,12 +1167,8 @@ The following options need to be configured:
                CONFIG_SUPPORT_EMMC_BOOT
                Enable some additional features of the eMMC boot partitions.
 
                CONFIG_SUPPORT_EMMC_BOOT
                Enable some additional features of the eMMC boot partitions.
 

-               CONFIG_SUPPORT_EMMC_RPMB
-               Enable the commands for reading, writing and programming the
-               key for the Replay Protection Memory Block partition in eMMC.
-

 - USB Device Firmware Update (DFU) class support:
 - USB Device Firmware Update (DFU) class support:

-               CONFIG_USB_FUNCTION_DFU
+               CONFIG_DFU_OVER_USB

                This enables the USB portion of the DFU USB class
 
                CONFIG_DFU_MMC
                This enables the USB portion of the DFU USB class
 
                CONFIG_DFU_MMC


@@ -1450,10 +1401,6 @@ The following options need to be configured:
                be at least 4MB.
 
 - MII/PHY support:
                be at least 4MB.
 
 - MII/PHY support:

-               CONFIG_PHY_ADDR
-
-               The address of PHY on MII bus.
-

                CONFIG_PHY_CLOCK_FREQ (ppc4xx)
 
                The clock frequency of the MII bus
                CONFIG_PHY_CLOCK_FREQ (ppc4xx)
 
                The clock frequency of the MII bus


@@ -1557,14 +1504,8 @@ The following options need to be configured:
                You can fine tune the DHCP functionality by defining
                CONFIG_BOOTP_* symbols:
 
                You can fine tune the DHCP functionality by defining
                CONFIG_BOOTP_* symbols:
 

-               CONFIG_BOOTP_SUBNETMASK
-               CONFIG_BOOTP_GATEWAY
-               CONFIG_BOOTP_HOSTNAME

                CONFIG_BOOTP_NISDOMAIN
                CONFIG_BOOTP_NISDOMAIN

-               CONFIG_BOOTP_BOOTPATH

                CONFIG_BOOTP_BOOTFILESIZE
                CONFIG_BOOTP_BOOTFILESIZE

-               CONFIG_BOOTP_DNS
-               CONFIG_BOOTP_DNS2

                CONFIG_BOOTP_SEND_HOSTNAME
                CONFIG_BOOTP_NTPSERVER
                CONFIG_BOOTP_TIMEOFFSET
                CONFIG_BOOTP_SEND_HOSTNAME
                CONFIG_BOOTP_NTPSERVER
                CONFIG_BOOTP_TIMEOFFSET


@@ -1580,15 +1521,6 @@ The following options need to be configured:
                to Link-local IP address configuration if the DHCP server
                is not available.
 
                to Link-local IP address configuration if the DHCP server
                is not available.
 

-               CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
-               serverip from a DHCP server, it is possible that more
-               than one DNS serverip is offered to the client.
-               If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
-               serverip will be stored in the additional environment
-               variable "dnsip2". The first DNS serverip is always
-               stored in the variable "dnsip", when CONFIG_BOOTP_DNS
-               is defined.
-

                CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
                to do a dynamic update of a DNS server. To do this, they
                need the hostname of the DHCP requester.
                CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
                to do a dynamic update of a DNS server. To do this, they
                need the hostname of the DHCP requester.


@@ -1618,6 +1550,15 @@ The following options need to be configured:
 
                See doc/README.link-local for more information.
 
 
                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
 
  - CDP Options:
                CONFIG_CDP_DEVICE_ID
 


@@ -2006,11 +1947,6 @@ The following options need to be configured:
                SPI EEPROM, also an instance works with Crystal A/D and
                D/As on the SACSng board)
 
                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
                CONFIG_SOFT_SPI
 
                Enables a software (bit-bang) SPI driver rather than


@@ -2029,11 +1965,6 @@ The following options need to be configured:
                Currently supported on some MPC8xxx processors.  For an
                example, see include/configs/mpc8349emds.h.
 
                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 */
                CONFIG_SYS_SPI_MXC_WAIT
                Timeout for waiting until spi transfer completed.
                default: (CONFIG_SYS_HZ/100)     /* 10 ms */


@@ -2183,16 +2114,6 @@ The following options need to be configured:
                currently only supports clearing the memory.
 
 - Error Recovery:
                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
                CONFIG_NET_RETRY_COUNT
 
                This variable defines the number of retries for


@@ -2212,10 +2133,6 @@ The following options need to be configured:
                #define CONFIG_NFS_TIMEOUT 10000UL
 
 - Command Interpreter:
                #define CONFIG_NFS_TIMEOUT 10000UL
 
 - Command Interpreter:

-               CONFIG_AUTO_COMPLETE
-
-               Enable auto completion of commands using TAB.
-

                CONFIG_SYS_PROMPT_HUSH_PS2
 
                This defines the secondary prompt string, which is
                CONFIG_SYS_PROMPT_HUSH_PS2
 
                This defines the secondary prompt string, which is


@@ -2244,12 +2161,6 @@ The following options need to be configured:
                symbols.
 
 - Command Line Editing and History:
                symbols.
 
 - Command Line Editing and History:

-               CONFIG_CMDLINE_EDITING
-
-               Enable editing and History functions for interactive
-               command line input operations
-
-- Command Line PS1/PS2 support:

                CONFIG_CMDLINE_PS_SUPPORT
 
                Enable support for changing the command prompt string
                CONFIG_CMDLINE_PS_SUPPORT
 
                Enable support for changing the command prompt string


@@ -2283,26 +2194,6 @@ The following options need to be configured:
                the environment like the "source" command or the
                boot command first.
 
                the environment like the "source" command or the
                boot command first.
 

-               CONFIG_ENV_VARS_UBOOT_CONFIG
-
-               Define this in order to add variables describing the
-               U-Boot build configuration to the default environment.
-               These will be named arch, cpu, board, vendor, and soc.
-
-               Enabling this option will cause the following to be defined:
-
-               - CONFIG_SYS_ARCH
-               - CONFIG_SYS_CPU
-               - CONFIG_SYS_BOARD
-               - CONFIG_SYS_VENDOR
-               - CONFIG_SYS_SOC
-
-               CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
-
-               Define this in order to add variables describing certain
-               run-time determined information about the hardware to the
-               environment.  These will be named board_name, board_rev.
-

                CONFIG_DELAY_ENVIRONMENT
 
                Normally the environment is loaded when the board is
                CONFIG_DELAY_ENVIRONMENT
 
                Normally the environment is loaded when the board is


@@ -2326,18 +2217,6 @@ The following options need to be configured:
                CONFIG_SF_DEFAULT_MODE          (see include/spi.h)
                CONFIG_SF_DEFAULT_SPEED         in Hz
 
                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
 
 - TFTP Fixed UDP Port:
                CONFIG_TFTP_PORT


@@ -2359,25 +2238,6 @@ The following options need to be configured:
                A better solution is to properly configure the firewall,
                but sometimes that is not allowed.
 
                A better solution is to properly configure the firewall,
                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
-               enable special bootcounter support on da850 based boards.
-               CONFIG_BOOTCOUNT_RAM
-               enable support for the bootcounter in RAM
-               CONFIG_BOOTCOUNT_I2C
-               enable support for the bootcounter on an i2c (like RTC) device.
-                       CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
-                       CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
-                                                   the bootcounter.
-                       CONFIG_BOOTCOUNT_ALEN = address len
-

 - Show boot progress:
                CONFIG_SHOW_BOOT_PROGRESS
 
 - Show boot progress:
                CONFIG_SHOW_BOOT_PROGRESS
 


@@ -2542,19 +2402,6 @@ FIT uImage format:
  -150  common/cmd_nand.c       Incorrect FIT image format
   151  common/cmd_nand.c       FIT image format OK
 
  -150  common/cmd_nand.c       Incorrect FIT image format
   151  common/cmd_nand.c       FIT image format OK
 

-- legacy image format:
-               CONFIG_IMAGE_FORMAT_LEGACY
-               enables the legacy image format support in U-Boot.
-
-               Default:
-               enabled if CONFIG_FIT_SIGNATURE is not defined.
-
-               CONFIG_DISABLE_IMAGE_LEGACY
-               disable the legacy image format
-
-               This define is introduced, as the legacy image format is
-               enabled per default for backward compatibility.
-

 - Standalone program support:
                CONFIG_STANDALONE_LOAD_ADDR
 
 - Standalone program support:
                CONFIG_STANDALONE_LOAD_ADDR
 


@@ -2597,12 +2444,6 @@ FIT uImage format:
                kernel. Needed for UBI support.
 
 - UBI support
                kernel. Needed for UBI support.
 
 - UBI support

-               CONFIG_UBI_SILENCE_MSG
-
-               Make the verbose messages from UBI stop printing.  This leaves
-               warnings and errors enabled.
-
-

                CONFIG_MTD_UBI_WL_THRESHOLD
                This parameter defines the maximum difference between the highest
                erase counter value and the lowest erase counter value of eraseblocks
                CONFIG_MTD_UBI_WL_THRESHOLD
                This parameter defines the maximum difference between the highest
                erase counter value and the lowest erase counter value of eraseblocks


@@ -2664,12 +2505,6 @@ FIT uImage format:
                Enable UBI fastmap debug
                default: 0
 
                Enable UBI fastmap debug
                default: 0
 

-- UBIFS support
-               CONFIG_UBIFS_SILENCE_MSG
-
-               Make the verbose messages from UBIFS stop printing.  This leaves
-               warnings and errors enabled.
-

 - SPL framework
                CONFIG_SPL
                Enable building of SPL globally.
 - SPL framework
                CONFIG_SPL
                Enable building of SPL globally.


@@ -2734,11 +2569,6 @@ FIT uImage format:
                CONFIG_SYS_SPL_MALLOC_SIZE
                The size of the malloc pool used in SPL.
 
                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
                CONFIG_SPL_OS_BOOT
                Enable booting directly to an OS from SPL.
                See also: doc/README.falcon


@@ -2795,6 +2625,10 @@ FIT uImage format:
                CONFIG_SPL_NAND_DRIVERS
                SPL uses normal NAND drivers, not minimal drivers.
 
                CONFIG_SPL_NAND_DRIVERS
                SPL uses normal NAND drivers, not minimal drivers.
 

+               CONFIG_SPL_NAND_IDENT
+               SPL uses the chip ID list to identify the NAND flash.
+               Requires CONFIG_SPL_NAND_BASE.
+

                CONFIG_SPL_NAND_ECC
                Include standard software ECC in the SPL
 
                CONFIG_SPL_NAND_ECC
                Include standard software ECC in the SPL
 


@@ -2856,7 +2690,7 @@ FIT uImage format:
                use an arch-specific makefile fragment instead, for
                example if more than one image needs to be produced.
 
                use an arch-specific makefile fragment instead, for
                example if more than one image needs to be produced.
 

-               CONFIG_FIT_SPL_PRINT
+               CONFIG_SPL_FIT_PRINT

                Printing information about a FIT image adds quite a bit of
                code to SPL. So this is normally disabled in SPL. Use this
                option to re-enable it. This will affect the output of the
                Printing information about a FIT image adds quite a bit of
                code to SPL. So this is normally disabled in SPL. Use this
                option to re-enable it. This will affect the output of the


@@ -2934,9 +2768,6 @@ Configuration Settings:
                Begin and End addresses of the area used by the
                simple memory test.
 
                Begin and End addresses of the area used by the
                simple memory test.
 

-- CONFIG_SYS_ALT_MEMTEST:
-               Enable an alternate, more extensive memory test.
-

 - CONFIG_SYS_MEMTEST_SCRATCH:
                Scratch address used by the alternate memory test
                You only need to set this if address zero isn't writeable
 - CONFIG_SYS_MEMTEST_SCRATCH:
                Scratch address used by the alternate memory test
                You only need to set this if address zero isn't writeable


@@ -3519,7 +3350,7 @@ Low Level (hardware related) configuration options:
                globally (CONFIG_CMD_MEMORY).
 
 - CONFIG_SKIP_LOWLEVEL_INIT
                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.
                low level initializations (like setting up the memory
                controller) are omitted and/or U-Boot does not
                relocate itself into RAM.


@@ -3562,9 +3393,6 @@ Low Level (hardware related) configuration options:
                If defined, the x86 reset vector code is included. This is not
                needed when U-Boot is running from Coreboot.
 
                If defined, the x86 reset vector code is included. This is not
                needed when U-Boot is running from Coreboot.
 

-- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
-               Enables the RTC32K OSC on AM33xx based plattforms
-

 - CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
                Option to disable subpage write in NAND driver
                driver that uses this:
 - CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
                Option to disable subpage write in NAND driver
                driver that uses this:


@@ -3727,6 +3555,11 @@ this behavior and build U-Boot to some external directory:
 Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
 variable.
 
 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
 
 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 +4806,22 @@ 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.
 
 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:
 ------------------
 
 Memory Management:
 ------------------
 


@@ -5134,8 +4983,9 @@ Coding Standards:
 -----------------
 
 All contributions to U-Boot should conform to the Linux kernel
 -----------------
 
 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
 
 Source files originating from a different project (for example the
 MTD subsystem) are generally exempt from these guidelines and are not


@@ -5167,7 +5017,7 @@ 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 <u-boot@lists.denx.de>;
 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
 
 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;

-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:
 
 When you send a patch, please include the following information with
 it: