opensbi.git/lib/utils/fdt/fdt_fixup.c, branch v1.4

lib: utils: fdt_fixup: Allow preserving PMU properties

2023-12-06T12:29:44Z

Add a Kconfig option to control PMU fixup, so the next stage software can dump the PMU node including event mapping information for debugging purposes. Signed-off-by: Yu Chien Peter Lin Reviewed-by: Atish Patra Reviewed-by: Anup Patel

platform/lib: Set no-map attribute on all PMP regions

2023-06-15T12:57:17Z

This reverts commit 6966ad0abe70 ("platform/lib: Allow the OS to map the regions that are protected by PMP"). It was thought at the time of this commit that allowing the kernel to map PMP protected regions was safe but it is actually not: for example, the hibernation process will try to access any linear mapping page and then will fault on such mapped PMP regions [1]. Another issue is that the device tree specification [2] states that a !no-map region must be declared as EfiBootServicesData/Code in the EFI memory map which would make the PMP protected regions reclaimable by the kernel. And to circumvent this, RISC-V edk2 diverges from the DT specification to declare those regions as EfiReserved. The no-map attribute was removed to allow the kernel to use hugepages larger than 2MB to map the linear mapping to improve the performance but actually a recent talk from Mike Rapoport [3] stated that the performance benefit was marginal. For all those reasons, let's mark all the PMP protected regions as "no-map". [1] https://lore.kernel.org/linux-riscv/CAAYs2=gQvkhTeioMmqRDVGjdtNF_vhB+vm_1dHJxPNi75YDQ_Q@mail.gmail.com/ [2] "3.5.4 /reserved-memory and UEFI" https://github.com/devicetree-org/devicetree-specification/releases/download/v0.4-rc1/devicetree-specification-v0.4-rc1.pdf [3] https://lwn.net/Articles/931406/ Signed-off-by: Alexandre Ghiti Reviewed-by: Atish Patra Reviewed-by: Xiang W

lib: utils: fdt_fixup: avoid buffer overrun

2023-04-07T05:52:25Z

fdt_reserved_memory_fixup() uses filtered_order[PMP_COUNT]. The index must not reach PMP_COUNT. Fixes: 199189bd1c17 ("lib: utils: Mark only the largest region as reserved in FDT") Addresses-Coverity-ID: 1536994 ("Out-of-bounds write") Signed-off-by: Heinrich Schuchardt Reviewed-by: Xiang W Reviewed-by: Anup Patel

lib: utils: fdt_fixup: Fix compile error

2023-02-27T05:19:09Z

When building with GCC-10 or older versions, it throws the following error: CC-DEP platform/generic/lib/utils/fdt/fdt_fixup.dep CC platform/generic/lib/utils/fdt/fdt_fixup.o lib/utils/fdt/fdt_fixup.c: In function 'fdt_reserved_memory_fixup': lib/utils/fdt/fdt_fixup.c:376:2: error: label at end of compound statement 376 | next_entry: | ^~~~~~~~~~ Remove the goto statement. Resolves: https://github.com/riscv-software-src/opensbi/issues/288 Signed-off-by: Yu Chien Peter Lin Signed-off-by: Xiang W Reviewed-by: Anup Patel Reviewed-by: Bin Meng

lib: utils: Mark only the largest region as reserved in FDT

2023-02-08T05:43:19Z

In commit 230278dcf, RX and RW regions were marked separately. When the RW region grows (e.g. with more harts) and it isn't a power-of-two, sbi_domain_memregion_init will upgrade the region to the next power-of-two. This will make RX and RW both start at the same base address, like so (with 64 harts): Domain0 Region01 : 0x0000000080000000-0x000000008001ffff M: (R,X) S/U: () Domain0 Region02 : 0x0000000080000000-0x00000000800fffff M: (R,W) S/U: () This doesn't break the permission enforcement because of static priorities in PMP but makes the kernel complain about the regions overlapping each other. Like so: [ 0.000000] OF: reserved mem: OVERLAP DETECTED! [ 0.000000] mmode_resv0@80000000 (0x0000000080000000--0x0000000080020000) \ overlaps with mmode_resv1@80000000 (0x0000000080000000--0x0000000080100000) To fix this warning, among the multiple regions having same base address but different sizes, add only the largest region as reserved region during fdt fixup. Fixes: 230278dcf (lib: sbi: Add separate entries for firmware RX and RW regions) Signed-off-by: Himanshu Chauhan Reviewed-by: Anup Patel

lib: utils: Add fdt_add_cpu_idle_states() helper function

2023-01-24T12:00:21Z

Since the availability and latency properties of CPU idle states depend on the specific SBI HSM implementation, it is appropriate that the idle states are added to the devicetree at runtime by that implementation. This helper function adds a platform-provided array of idle states to the devicetree, following the SBI idle state binding. Reviewed-by: Anup Patel Signed-off-by: Samuel Holland

lib: utils: Fix reserved memory node for firmware memory

2023-01-22T12:19:10Z

The commit 9e0ba090 introduced more fine grained permissions for memory regions and did not update the fdt_reserved_memory_fixup() function. As a result, the fdt_reserved_memory_fixup continued to use the older coarse permissions which causes the reserved memory node to be not inserted into the DT. To fix the above issue, we correct the flags used for memory region permission checks in the fdt_reserved_memory_fixup() function. Fixes: 9e0ba090 ("include: sbi: Fine grain the permissions for M and SU modes") Signed-off-by: Mayuresh Chitale Reviewed-by: Anup Patel

lib: utils: Add fdt_fixup_node() helper function

2022-12-05T12:24:45Z

Add a helper function fdt_fixup_node() based on the compatible string. This will avoid code duplication for every new node fixup being added. Signed-off-by: Lad Prabhakar Reviewed-by: Bin Meng Reviewed-by: Xiang W Reviewed-by: Anup Patel

lib: utils: check if CPU node is enabled

2022-05-14T04:46:50Z

Ignore CPU nodes in FDT that are not enabled. Signed-off-by: Jan Remes Reviewed-by: Anup Patel

lib: utils: Disable appropriate APLIC DT nodes in fdt_fixups()

2022-02-15T15:09:15Z

We should disable APLIC DT nodes in fdt_fixups() which are not accessible to the next booting stage based on currently assigned domain. Signed-off-by: Anup Patel Signed-off-by: Anup Patel Reviewed-by: Atish Patra