kernel/arch/powerpc/platforms/microwatt/setup.c, branch linux-6.2.y

powerpc/microwatt: wire up rng during setup_arch()

2022-06-18T00:19:10Z

The platform's RNG must be available before random_init() in order to be useful for initial seeding, which in turn means that it needs to be called from setup_arch(), rather than from an init call. Fortunately, each platform already has a setup_arch function pointer, which means it's easy to wire this up. This commit also removes some noisy log messages that don't add much. Fixes: c25769fddaec ("powerpc/microwatt: Add support for hardware random number generator") Cc: stable@vger.kernel.org # v5.14+ Signed-off-by: Jason A. Donenfeld Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220611151015.548325-2-Jason@zx2c4.com

powerpc/microwatt: Use standard 16550 UART for console

2021-06-21T11:16:31Z

This adds support to the Microwatt platform to use the standard 16550-style UART which available in the standalone Microwatt FPGA. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Paul Mackerras Reviewed-by: Segher Boessenkool Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/YMwXGCTzedpQje7r@thinks.paulus.ozlabs.org

powerpc/xics: Add a native ICS backend for microwatt

2021-06-21T11:15:58Z

This is a simple native ICS backend that matches the layout of the Microwatt implementation of ICS. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Paul Mackerras Reviewed-by: Segher Boessenkool [mpe: Add empty ics_native_init() to unbreak non-microwatt builds] Signed-off-by: Michael Ellerman fixup-ics Link: https://lore.kernel.org/r/YMwW8cxrwB2W5EUN@thinks.paulus.ozlabs.org

powerpc/microwatt: Populate platform bus from device-tree

2021-06-21T11:15:26Z

Just like any other embedded platform. Add an empty soc node. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Paul Mackerras Reviewed-by: Segher Boessenkool Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/YMwWx98+PMibZq/G@thinks.paulus.ozlabs.org

powerpc: Add Microwatt platform

2021-06-21T11:15:26Z

Microwatt is a FPGA-based implementation of the Power ISA. It currently only implements little-endian 64-bit mode, and does not (yet) support SMP, VMX, VSX or transactional memory. It has an optional FPU, and an optional MMU (required for running Linux, obviously) which implements a configurable radix tree but not hypervisor mode or nested radix translation. This adds a new machine type to support FPGA-based SoCs with a Microwatt core. CONFIG_MATH_EMULATION can be selected for Microwatt SOCs which don't have the FPU. Signed-off-by: Paul Mackerras Reviewed-by: Nicholas Piggin Reviewed-by: Segher Boessenkool Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/YMwWbZVREsVug9R0@thinks.paulus.ozlabs.org