v3: - Fix build error on some configs. - Reword binding. - Added note about alternatives in cover letter (see below) v2: - Add note on what "phram" means in binding. - Use /schemas/mtd/mtd.yaml instead of relative pathUse /schemas/mtd/mtd.yaml instead of relative path in binding. The phram driver in the MTD subsystem can be used to allow the kernel to use an MTD or (via mtdblock) a block device in RAM (with the contents loaded by a bootloader for example). This series has some improvements to make it more usable by adding device tree support and to significantly improve its performance by using cached mappings when possible. I use this feature to pass the squashfs rootfs to the kernel when booting from RAM. The boot is much faster and requires less memory than initrd (which is on top of that being deprecated), and it allows the same disk images to be used when booting from RAM, unlike initramfs. If there is no interest in extending the phram driver to support this, an option is to use a new custom block driver. I have patches for that too. That will not support MTDs of course, but it works for block devices and it is faster and smaller than mtdblock + MTD + phram. Cc: linux-mtd@xxxxxxxxxxxxxxxxxxx Cc: devicetree@xxxxxxxxxxxxxxx Cc: robh+dt@xxxxxxxxxx Cc: krzk+dt@xxxxxxxxxx Cc: frowand.list@xxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Vincent Whitchurch (4): mtd: core: Check devicetree alias for index dt-bindings: reserved-memory: Support MTD/block device mtd: phram: Allow probing via reserved-memory mtd: phram: Allow cached mappings .../bindings/reserved-memory/phram.yaml | 47 +++++++++++ drivers/mtd/devices/phram.c | 78 +++++++++++++++++-- drivers/mtd/mtdcore.c | 11 ++- drivers/of/platform.c | 1 + 4 files changed, 129 insertions(+), 8 deletions(-) create mode 100644 Documentation/devicetree/bindings/reserved-memory/phram.yaml -- 2.34.1
