diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/README.clang | 56 | ||||
| -rw-r--r-- | doc/README.fsl-esdhc | 5 | ||||
| -rw-r--r-- | doc/README.scrapyard | 14 | ||||
| -rw-r--r-- | doc/device-tree-bindings/serial/ns16550.txt | 10 | ||||
| -rw-r--r-- | doc/device-tree-bindings/serial/sandbox-serial.txt | 13 |
5 files changed, 92 insertions, 6 deletions
diff --git a/doc/README.clang b/doc/README.clang new file mode 100644 index 0000000000..9ad689f071 --- /dev/null +++ b/doc/README.clang @@ -0,0 +1,56 @@ +The biggest problem when trying to compile U-boot with clang is that +almost all archs rely on storing gd in a global register and clang user +manual states: "clang does not support global register variables; this +is unlikely to be implemented soon because it requires additional LLVM +backend support." + +Since version 3.4 the ARM backend can be instructed to leave r9 alone. +Global registers themselves are not supported so some inline assembly is +used to get its value. This does lead to larger code then strictly +necessary, but at least works. + +NOTE: target compilation only work for _some_ ARM boards at the moment. +Also Aarch64 is not supported: Most notably boards which aren't using +the generic board will fail to compile, but since those are expected +to be converted this will solve itself. Boards which reassign gd in c +will also fail to compile, but there is in no strict reason to do so +in the ARM world, since crt0.S takes care of this. These assignments +can be avoided by changing the init calls but this is not in mainline yet. + +NOTE: without the -mllvm -arm-use-movt=0 flags u-boot will compile +fine, but llvm might hardcode addresses in movw / movt pairs, which +cannot be relocated and u-boot will fail at runtime. + +Debian (based) +-------------- +Binary packages can be installed as usual, e.g.: +sudo apt-get install clang + +To compile U-Boot with clang on linux without IAS use e.g.: +export TRIPLET=arm-linux-gnueabi && export CROSS_COMPILE="$TRIPLET-" +make HOSTCC=clang CC="clang -target $TRIPLET -mllvm -arm-use-movt=0 -no-integrated-as" rpi_b_defconfig +make HOSTCC=clang CC="clang -target $TRIPLET -mllvm -arm-use-movt=0 -no-integrated-as" all V=1 -j8 + +FreeBSD 11 (Current): +-------------------- +Since llvm 3.4 is currently in the base system, the integrated as is +incapable of building U-Boot. Therefore gas from devel/arm-eabi-binutils +is used instead. It needs a symlinks to be picked up correctly though: + +ln -s /usr/local/bin/arm-eabi-as /usr/bin/arm-freebsd-eabi-as + +# The following commands compile U-Boot using the clang xdev toolchain. +# NOTE: CROSS_COMPILE and target differ on purpose! +export CROSS_COMPILE=arm-eabi- +gmake CC="clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0" rpi_b_defconfig +gmake CC="clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0" -j8 + +Given that u-boot will default to gcc, above commands can be +simplified with a simple wrapper script, listed below. + +/usr/local/bin/arm-eabi-gcc +--- +#!/bin/sh + +exec clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0 "$@" + diff --git a/doc/README.fsl-esdhc b/doc/README.fsl-esdhc new file mode 100644 index 0000000000..b70f271d1a --- /dev/null +++ b/doc/README.fsl-esdhc @@ -0,0 +1,5 @@ +CONFIG_SYS_FSL_ESDHC_LE means ESDHC IP is in little-endian mode. +CONFIG_SYS_FSL_ESDHC_BE means ESDHC IP is in big-endian mode. + +Accessing ESDHC registers can be determined by ESDHC IP's endian +mode or processor's endian mode. diff --git a/doc/README.scrapyard b/doc/README.scrapyard index 7ef5a225d9..2f5034f362 100644 --- a/doc/README.scrapyard +++ b/doc/README.scrapyard @@ -12,12 +12,14 @@ The list should be sorted in reverse chronological order. Board Arch CPU Commit Removed Last known maintainer/contact ================================================================================================= -flagadm powerpc mpc8xx - - Kári Davíðsson <kd@flaga.is> -gen860t powerpc mpc8xx - - Keith Outwater <Keith_Outwater@mvis.com> -sixnet powerpc mpc8xx - - Dave Ellis <DGE@sixnetio.com> -svm_sc8xx powerpc mpc8xx - - John Zhan <zhanz@sinovee.com> -stxxtc powerpc mpc8xx - - Dan Malek <dan@embeddedalley.com> -omap5912osk arm arm926ejs - - Rishi Bhattacharya <rishi@ti.com> +PK1C20 nios2 - 70fbc461 2014-08-24 Scott McNutt <smcnutt@psyent.com> +PCI5441 nios2 - 70fbc461 2014-08-24 Scott McNutt <smcnutt@psyent.com> +flagadm powerpc mpc8xx aec6f8c5 2014-08-22 Kári Davíðsson <kd@flaga.is> +gen860t powerpc mpc8xx 6bde1ec1 2014-08-22 Keith Outwater <Keith_Outwater@mvis.com> +sixnet powerpc mpc8xx 4723ce49 2014-08-22 Dave Ellis <DGE@sixnetio.com> +svm_sc8xx powerpc mpc8xx d1a4aafd 2014-08-22 John Zhan <zhanz@sinovee.com> +stxxtc powerpc mpc8xx 0ace4d9d 2014-08-22 Dan Malek <dan@embeddedalley.com> +omap5912osk arm arm926ejs 62d636aa 2014-08-22 Rishi Bhattacharya <rishi@ti.com> p1023rds powerpc mpc85xx d0bc5140 2014-07-22 Roy Zang <tie-fei.zang@freescale.com> spc1920 powerpc mpc8xx 98ad54be 2014-07-07 v37 powerpc mpc8xx b8c1438a 2014-07-07 diff --git a/doc/device-tree-bindings/serial/ns16550.txt b/doc/device-tree-bindings/serial/ns16550.txt new file mode 100644 index 0000000000..ef0b9aee6d --- /dev/null +++ b/doc/device-tree-bindings/serial/ns16550.txt @@ -0,0 +1,10 @@ +NS16550 UART + +This UART driver supports many chip variants and is used in mamy SoCs. + +Required properties: +- compatible: "ns16550" or "nvidia,tegra20-uart" +- reg: start address and size of registers +- reg-shift: shift value indicating register size: 0=byte, 1=16bit,2=32bit etc. +- clock-frequency: input clock frequency for the UART (used to calculate the + baud rate divisor) diff --git a/doc/device-tree-bindings/serial/sandbox-serial.txt b/doc/device-tree-bindings/serial/sandbox-serial.txt new file mode 100644 index 0000000000..f429c90421 --- /dev/null +++ b/doc/device-tree-bindings/serial/sandbox-serial.txt @@ -0,0 +1,13 @@ +Sandbox serial + +The sandbox serial device is an emulated device which displays its output +on the host machine's console, and accepts input from its keyboard. + +Required properties: + compatible: "sandbox,serial" + +Optional properties: + sandbox,text-colour: If present, this is the colour of the console text. + Supported values are: + "black", "red", "green", "yellow", "blue", "megenta", "cyan", + "white" |