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-rw-r--r--Documentation/arm/CCN.txt17
-rw-r--r--Documentation/arm/Samsung/Bootloader-interface.txt53
-rw-r--r--Documentation/arm/stm32/overview.txt32
-rw-r--r--Documentation/arm/stm32/stm32f429-overview.txt22
-rw-r--r--Documentation/arm/vlocks.txt2
5 files changed, 118 insertions, 8 deletions
diff --git a/Documentation/arm/CCN.txt b/Documentation/arm/CCN.txt
index 0632b3aad83e..ffca443a19b4 100644
--- a/Documentation/arm/CCN.txt
+++ b/Documentation/arm/CCN.txt
@@ -33,20 +33,23 @@ directory, with first 8 configurable by user and additional
Cycle counter is described by a "type" value 0xff and does
not require any other settings.
+The driver also provides a "cpumask" sysfs attribute, which contains
+a single CPU ID, of the processor which will be used to handle all
+the CCN PMU events. It is recommended that the user space tools
+request the events on this processor (if not, the perf_event->cpu value
+will be overwritten anyway). In case of this processor being offlined,
+the events are migrated to another one and the attribute is updated.
+
Example of perf tool use:
/ # perf list | grep ccn
ccn/cycles/ [Kernel PMU event]
<...>
- ccn/xp_valid_flit/ [Kernel PMU event]
+ ccn/xp_valid_flit,xp=?,port=?,vc=?,dir=?/ [Kernel PMU event]
<...>
-/ # perf stat -C 0 -e ccn/cycles/,ccn/xp_valid_flit,xp=1,port=0,vc=1,dir=1/ \
+/ # perf stat -a -e ccn/cycles/,ccn/xp_valid_flit,xp=1,port=0,vc=1,dir=1/ \
sleep 1
The driver does not support sampling, therefore "perf record" will
-not work. Also notice that only single cpu is being selected
-("-C 0") - this is because perf framework does not support
-"non-CPU related" counters (yet?) so system-wide session ("-a")
-would try (and in most cases fail) to set up the same event
-per each CPU.
+not work. Per-task (without "-a") perf sessions are not supported.
diff --git a/Documentation/arm/Samsung/Bootloader-interface.txt b/Documentation/arm/Samsung/Bootloader-interface.txt
new file mode 100644
index 000000000000..b96ead9a6919
--- /dev/null
+++ b/Documentation/arm/Samsung/Bootloader-interface.txt
@@ -0,0 +1,53 @@
+ Interface between kernel and boot loaders on Exynos boards
+ ==========================================================
+
+Author: Krzysztof Kozlowski
+Date : 6 June 2015
+
+The document tries to describe currently used interface between Linux kernel
+and boot loaders on Samsung Exynos based boards. This is not a definition
+of interface but rather a description of existing state, a reference
+for information purpose only.
+
+In the document "boot loader" means any of following: U-boot, proprietary
+SBOOT or any other firmware for ARMv7 and ARMv8 initializing the board before
+executing kernel.
+
+
+1. Non-Secure mode
+Address: sysram_ns_base_addr
+Offset Value Purpose
+=============================================================================
+0x08 exynos_cpu_resume_ns System suspend
+0x0c 0x00000bad (Magic cookie) System suspend
+0x1c exynos4_secondary_startup Secondary CPU boot
+0x1c + 4*cpu exynos4_secondary_startup (Exynos4412) Secondary CPU boot
+0x20 0xfcba0d10 (Magic cookie) AFTR
+0x24 exynos_cpu_resume_ns AFTR
+0x28 + 4*cpu 0x8 (Magic cookie, Exynos3250) AFTR
+
+
+2. Secure mode
+Address: sysram_base_addr
+Offset Value Purpose
+=============================================================================
+0x00 exynos4_secondary_startup Secondary CPU boot
+0x04 exynos4_secondary_startup (Exynos542x) Secondary CPU boot
+4*cpu exynos4_secondary_startup (Exynos4412) Secondary CPU boot
+0x20 exynos_cpu_resume (Exynos4210 r1.0) AFTR
+0x24 0xfcba0d10 (Magic cookie, Exynos4210 r1.0) AFTR
+
+Address: pmu_base_addr
+Offset Value Purpose
+=============================================================================
+0x0800 exynos_cpu_resume AFTR
+0x0814 exynos4_secondary_startup (Exynos4210 r1.1) Secondary CPU boot
+0x0818 0xfcba0d10 (Magic cookie, Exynos4210 r1.1) AFTR
+0x081C exynos_cpu_resume (Exynos4210 r1.1) AFTR
+
+
+3. Other (regardless of secure/non-secure mode)
+Address: pmu_base_addr
+Offset Value Purpose
+=============================================================================
+0x0908 Non-zero (only Exynos3250) Secondary CPU boot up indicator
diff --git a/Documentation/arm/stm32/overview.txt b/Documentation/arm/stm32/overview.txt
new file mode 100644
index 000000000000..09aed5588d7c
--- /dev/null
+++ b/Documentation/arm/stm32/overview.txt
@@ -0,0 +1,32 @@
+ STM32 ARM Linux Overview
+ ========================
+
+Introduction
+------------
+
+ The STMicroelectronics family of Cortex-M based MCUs are supported by the
+ 'STM32' platform of ARM Linux. Currently only the STM32F429 is supported.
+
+
+Configuration
+-------------
+
+ A generic configuration is provided for STM32 family, and can be used as the
+ default by
+ make stm32_defconfig
+
+Layout
+------
+
+ All the files for multiple machine families are located in the platform code
+ contained in arch/arm/mach-stm32
+
+ There is a generic board board-dt.c in the mach folder which support
+ Flattened Device Tree, which means, it works with any compatible board with
+ Device Trees.
+
+
+Document Author
+---------------
+
+ Maxime Coquelin <mcoquelin.stm32@gmail.com>
diff --git a/Documentation/arm/stm32/stm32f429-overview.txt b/Documentation/arm/stm32/stm32f429-overview.txt
new file mode 100644
index 000000000000..5206822bd8ef
--- /dev/null
+++ b/Documentation/arm/stm32/stm32f429-overview.txt
@@ -0,0 +1,22 @@
+ STM32F429 Overview
+ ==================
+
+ Introduction
+ ------------
+ The STM32F429 is a Cortex-M4 MCU aimed at various applications.
+ It features:
+ - ARM Cortex-M4 up to 180MHz with FPU
+ - 2MB internal Flash Memory
+ - External memory support through FMC controller (PSRAM, SDRAM, NOR, NAND)
+ - I2C, SPI, SAI, CAN, USB OTG, Ethernet controllers
+ - LCD controller & Camera interface
+ - Cryptographic processor
+
+ Resources
+ ---------
+ Datasheet and reference manual are publicly available on ST website:
+ - http://www.st.com/web/en/catalog/mmc/FM141/SC1169/SS1577/LN1806?ecmp=stm32f429-439_pron_pr-ces2014_nov2013
+
+ Document Author
+ ---------------
+ Maxime Coquelin <mcoquelin.stm32@gmail.com>
diff --git a/Documentation/arm/vlocks.txt b/Documentation/arm/vlocks.txt
index 415960a9bab0..45731672c564 100644
--- a/Documentation/arm/vlocks.txt
+++ b/Documentation/arm/vlocks.txt
@@ -206,6 +206,6 @@ References
[1] Lamport, L. "A New Solution of Dijkstra's Concurrent Programming
Problem", Communications of the ACM 17, 8 (August 1974), 453-455.
- http://en.wikipedia.org/wiki/Lamport%27s_bakery_algorithm
+ https://en.wikipedia.org/wiki/Lamport%27s_bakery_algorithm
[2] linux/arch/arm/common/vlock.S, www.kernel.org.