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It seems that the "cpu_clk" was carried over from the meson8b clock controller driver. On Meson GX (GXBB/GXL/GXM) the registers which are used by the cpu_clk have a different purpose (in other words: they don't control the CPU clock anymore). HHI_SYS_CPU_CLK_CNTL1 bits 31:24 are reserved according to the public S905 datasheet, while bit 23 is the "A53_trace_clk_DIS" gate (which according to the datasheet should only be used in case a silicon bug is discovered) and bits 22:20 are a divider (A53_trace_clk). The meson clk-cpu code however expects that bits 28:20 are reserved for a divider (according to the public S805 datasheet this "SCALE_DIV: This value represents an N+1 divider of the input clock."). The CPU clock on Meson GX SoCs is provided by the SCPI DVFS clock driver instead. Two examples from a Meson GXL S905X SoC: - vcpu (SCPI DVFS clock 0) rate: 1000000000 / cpu_clk rate: 708000000 - vcpu (SCPI DVFS clock 0) rate: 1512000000 / cpu_clk rate: 708000000 Unfortunately the CLKID_CPUCLK was already exported (but is currently not used) to DT. Due to the removal of this clock definition there is now a hole in the clk_hw_onecell_data (which is not a problem because this case is already handled in gxbb_clkc_probe). Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
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.