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Pull "Renesas ARM Based SoC Updates for v4.17" from Simon Horman:01d675f159ARM: shmobile: rcar-gen2: Add watchdog support58adf1ba0dARM: shmobile: Add watchdog support * SoC - Identify R-Car V3H (r8a77980) and M3N (r8a77965) - Enable R-Car Gen2 regulator quirk for Stout board with H3 (r8a7790) SoC Marek Vaust says "Regulator setup is suboptimal on H2 Stout too. The Stout newly has two DA9210 regulators, so the quirk is extended to handle another DA9210 at i2c address 0x70." - Add watchdog support This is the SoC portion of the following solution. It is not yet enabled in DT as it is not functional without clock dependencies in place. Fabrizio Castro says "this series has been around for some time as RFC, and it has collected useful comments from the community along the way. The solution proposed by this patch set works for most R-Car Gen2 and RZ/G1 devices, but not all of them. We now know that for some R-Car Gen2 early revisions there is no proper software fix. Anyway, no product has been built around early revisions, but development boards mounting early revisions (basically prototypes) are still out there. As a result, this series isn't enabling the internal watchdog on R-Car Gen2 boards, developers may enable it in board specific device trees if needed. This series has been tested by me on the iwg20d, iwg22d, Lager, Alt, and Koelsch boards. The problem =========== To deal with SMP on R-Car Gen2 and RZ/G1, we install a reset vector to ICRAM1 and we program the [S]BAR registers so that when we turn ON the non-boot CPUs they are redirected to the reset vector installed by Linux in ICRAM1, and eventually they continue the execution to RAM, where the SMP bring-up code will take care of the rest. The content of the [S]BAR registers survives a watchdog triggered reset, and as such after the watchdog fires the boot core will try and execute the SMP bring-up code instead of jumping to the bootrom code. The fix ======= The main strategy for the solution is to let the reset vector decide if it needs to jump to shmobile_boot_fn or to the bootrom code. In a watchdog triggered reset scenario, since the [S]BAR registers keep their values, the boot CPU will jump into the newly designed reset vector, the assembly routine will eventually test WOVF (a bit in register RWTCSRA that indicates if the watchdog counter has overflown, the value of this bit gets retained in this scenario), and jump to the bootrom code which will in turn load up the bootloader, etc. When bringing up SMP or using CPU hotplug, the reset vector will jump to shmobile_boot_fn instead." * R-Car Rst - Add support for R-Car V3H (r8a77980) and V3H (r8a77980) * R-Car SYSC - Mark rcar_sysc_matches[] __initconst Geert Uytterhoeven says "This frees another 1764 bytes (arm32/shmobile_defconfig) or 1000 bytes (arm64/renesas_defconfig) of memory after kernel init." - Fix power area parents Sergei Shtylyov says "According to the figure 9.2(b) of the R-Car Series, 3rd Generation User’s Manual: Hardware Rev. 0.80 the A2IRn and A2SCn power areas in R8A77970 have the A3IR area as a parent, thus the SYSC driver has those parents wrong.." - Add support for R-Car V3H (r8a77980) and V3H (r8a77980) * tag 'renesas-soc-for-v4.17' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/horms/renesas: ARM: shmobile: rcar-gen2: Add watchdog support ARM: shmobile: Add watchdog support ARM: shmobile: rcar-gen2: Fix error check in regulator quirk soc: renesas: rcar-rst: Add support for R-Car M3-N ARM: shmobile: stout: enable R-Car Gen2 regulator quirk soc: renesas: rcar-sysc: Add R-Car M3-N support soc: renesas: Identify R-Car M3-N soc: renesas: rcar-sysc: add R8A77980 support dt-bindings: power: add R8A77980 SYSC power domain definitions soc: renesas: r8a77970-sysc: fix power area parents soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2 soc: renesas: rcar-rst: add R8A77980 support soc: renesas: identify R-Car V3H soc: renesas: rcar-sysc: Mark rcar_sysc_matches[] __initconst
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.