Commit Graph

29 Commits

Author SHA1 Message Date
Heinrich Schuchardt 73344d4724 lib: utils: check correct value in fdt_node_offset_by_compatible
After calling fdt_node_offset_by_compatible() we must check its return
value and not an unrelated value.

Addresses-Coverity-ID: 1584993 Logically dead code
Fixes: 67ce5a763c ("platform: generic: Add support for specify coldboot harts in DT")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2024-04-10 09:38:26 +05:30
Cheng Yang 67ce5a763c platform: generic: Add support for specify coldboot harts in DT
Added support for the generic platform to specify the set of coldboot
hart in DT. If not specified in DT, all harts are allowed to coldboot
as before.

The functions related to sbi_hartmask are not available before coldboot,
so I used bitmap, and added a new bitmap_test() function to test whether
a certain bit of the bitmap is set.

Signed-off-by: Cheng Yang <yangcheng.work@foxmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2024-02-20 15:49:36 +05:30
Yu Chien Peter Lin 0b3262efc6 lib: utils: fdt_fixup: Allow preserving PMU properties
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 <peterlin@andestech.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2023-12-06 17:59:44 +05:30
Alexandre Ghiti 8153b2622b platform/lib: Set no-map attribute on all PMP regions
This reverts commit 6966ad0abe ("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 <alexghiti@rivosinc.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
2023-06-15 18:27:17 +05:30
Heinrich Schuchardt 2868f26131 lib: utils: fdt_fixup: avoid buffer overrun
fdt_reserved_memory_fixup() uses filtered_order[PMP_COUNT]. The index
must not reach PMP_COUNT.

Fixes: 199189bd1c ("lib: utils: Mark only the largest region as reserved in FDT")
Addresses-Coverity-ID: 1536994 ("Out-of-bounds write")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2023-04-07 11:22:25 +05:30
Xiang W 6861ee996c lib: utils: fdt_fixup: Fix compile error
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 <peterlin@andestech.com>
Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
2023-02-27 10:49:09 +05:30
Himanshu Chauhan 199189bd1c lib: utils: Mark only the largest region as reserved in FDT
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 <hchauhan@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2023-02-08 11:13:19 +05:30
Samuel Holland 33bf917460 lib: utils: Add fdt_add_cpu_idle_states() helper function
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 <anup@brainfault.org>
Signed-off-by: Samuel Holland <samuel@sholland.org>
2023-01-24 17:30:21 +05:30
Mayuresh Chitale a990309fa3 lib: utils: Fix reserved memory node for firmware memory
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 <mchitale@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2023-01-22 17:49:10 +05:30
Lad Prabhakar e9775120f5 lib: utils: Add fdt_fixup_node() helper function
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 <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2022-12-05 17:54:45 +05:30
Jan Remes 616da52e18 lib: utils: check if CPU node is enabled
Ignore CPU nodes in FDT that are not enabled.

Signed-off-by: Jan Remes <jan.remes@codasip.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
2022-05-14 10:16:50 +05:30
Anup Patel 8e2ef4f7af lib: utils: Disable appropriate APLIC DT nodes in fdt_fixups()
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 <anup.patel@wdc.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
2022-02-15 20:39:15 +05:30
Anup Patel 7127aaaaf7 lib: utils: Disable appropriate IMSIC DT nodes in fdt_fixups()
We should disable IMSIC DT nodes in fdt_fixups() which are not
accessible to the next booting stage based on currently assigned
domain.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
2022-02-15 20:37:27 +05:30
Atish Patra ae72ec0915 utils: fdt: Add fdt helper functions to parse PMU DT nodes
The PMU DT node bindings are defined in docs/pmu_support.md
Add few fdt helper functions to parse the DT node and update the
event-counter mapping tables.

Reviewed-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
2021-07-11 10:27:57 +05:30
Bin Meng 4edc822407 lib/utils: Support fixing up the official DT bindings of PLIC
Current fdt_plic_fixup() only does necessary fix-up against the legacy
"riscv,plic0" node. The upstream Linux kernel defines its official DT
bindings which uses "sifive,plic-1.0.0" as the compatible string and
we should check that first, and if not present fall back to legacy.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2021-04-01 10:31:11 +05:30
Bin Meng ca3f35821b lib/utils: Drop the 'compat' parameter of fdt_plic_fixup()
At present fdt_plic_fixup() accepts a 'compat' parameter for PLIC
compatible string. In preparation to support the new DT bindings,
drop this and use "riscv,plic0" directly in fdt_plic_fixup().

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2021-04-01 10:27:28 +05:30
Anup Patel 5fd99dbdaa lib: utils: Update fdt_cpu_fixup() to use current domain
The fdt_cpu_fixup() should disable a HART in DT if the HART
is not assigned to the current HART domain. This patch updates
fdt_cpu_fixup() accordingly.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20 14:04:51 +05:30
Anup Patel 5edbb7cda1 lib: utils: Update fdt_reserved_memory_fixup() to use current domain
Now that each HART is mapped to a domain having a set of memory
regions, we update fdt_reserved_memory_fixup() to use domain memory
regions for adding reserved memory nodes in device tree.

We also change reserved memory node name prefix from "mmode_pmp"
to "mmode_resv" because domain memory regions can impact other
hardware configurations (such as IOPMP, etc) along with PMP.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20 14:04:43 +05:30
Anup Patel 9f935a4a43 lib: utils: Improve fdt_cpu_fixup() implementation
The fdt_cpu_fixup() should work fine even if HARTs without MMU
are not marked invalid by platform support code.

In future, we plan to treat HARTs without MMU as valid in the
generic platform support so that we can hold these HARTs in
HSM STOPPED state.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-16 09:05:27 +05:30
Anup Patel 7b0b289887 lib: sbi: Remove redundant SBI_HART_HAS_PMP feature
The SBI_HART_HAS_PMP feature is redundant because we already
have number of PMP regions returned by sbi_hart_pmp_count().

Checking whether PMP is supported for a HART can be simply done
by checking non-zero value returned by sbi_hart_pmp_count().

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-01 10:28:26 +05:30
Bin Meng a5f9104330 lib/utils: fdt: Update FDT expand size to 1024 for reserved memory node
Currently 256 bytes is used for the FDT expand size when fixing up
reserved memory node. Increase it to 1024 bytes with an estimated
size of 64 bytes per PMP memory region by 16 regions in total.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-07-06 14:05:29 +05:30
Alexandre Ghiti 6966ad0abe platform/lib: Allow the OS to map the regions that are protected by PMP
This is achieved by removing the 'no-map' property from the
'reserved-memory' node when PMP is present, otherwise we keep it as it
offers a small protection if the OS does not map this region at all.
A new callback in platform_override is introduced and allows to fixup the
device-tree. It is used here to override this new default behaviour on
SiFive Fu540 platforms that has an erratum that prevents S-mode software
to access a PMP protected region using 1GB page table mapping.

If PMP is present, telling the OS not to map the reserved regions does not
add much protection since it only avoids access to regions that are already
protected by PMP. But by not allowing the OS to map those regions, it
creates holes in the OS system memory map and prevents the use of
hugepages which would generate, among other benefits, less TLB miss.

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-06-15 09:25:44 +05:30
Anup Patel a38bea9341 lib: sbi_hart: Detect number of supported PMP regions
It is not mandatory for a RISC-V systems to implement all PMP
regions so we have to check all PMPADDRx CSRs to determine excat
number of supported PMP regions.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
2020-05-19 09:19:48 +05:30
Anup Patel 63b0f5f71a include: sbi: Use scratch pointer as parmeter in HART feature APIs
It makes more sense to have scratch pointer as parameter in
HART feature APIs because:
1. We already have scratch pointer at places where these APIs
   are used.
2. This is consistent with lot of other APIs in sbi_hart.h

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-05-19 09:19:42 +05:30
Atish Patra b2df751acf platform: Move platform features to hart
PMP & performance counters belong to a hart rather than a platform.
In addition to that, these features enable reading/writing from a
particular csr. Thus, they can be detected and set at runtime rather
than compile time.

Move PMP/MCOUNTEREN/SCOUNTEREN features to hart and detect them at runtime.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Jonathan Balkind <jbalkind@cs.princeton.edu>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-05-10 10:05:41 +05:30
Atish Patra 79d0fadb06 lib: utils: Update reserved memory fdt node even if PMP is not present
As per RISC-V ISA, pmp is not mandatory. Currently, we only add reserved
memory node in DT only if PMP is present. That allows supervisor to access
the memory where OpenSBI continue to exist without realizing it for non-pmp
based platforms. It may result in corrupting OpenSBI. That's why OpenSBI
should at least let the supervisor know where it continue to exist.
This a best effort service provided by OpenSBI expecting that supervisor
software is not buggy and properly sets up its memory after parsing the
reserved-memory device tree node.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-05-10 10:00:02 +05:30
Anup Patel 19e966b862 lib: utils: Add fdt_parse_hart_id() function
Parsing HART id from a CPU DT node is a common requirement for
RISC-V systems. The newly added fdt_parse_hart_id() also helps
reduce duplicate code between fdt_cpu_fixup() function and
fdt_parse_hart_count() function.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-05-01 09:43:07 +05:30
Anup Patel 160c88535f lib: utils: Improve fdt_cpu_fixup() implementation
Currently, the fdt_cpu_fixup() implementation assumes:
1. We have one CPU DT for each HART under /cpus DT node
2. The CPU DT nodes are named sequentially (i.e cpu@0,
   cpu@1, ...) which is not true for discontinuous and
   sparse HART ids (i.e. cpu@0, cpu@4, cpu@5). Generally,
   CPU DT node are named based on HART id and not HART
   index

If any of the above assumptions are violated then the
fdt_cpu_fixup() will not work.

This improves fdt_cpu_fixup() implementation and makes
it independent of above assumptions.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-03-28 13:31:50 +05:30
Atish Patra 040e4e2ec2 lib: utils: Move fdt fixup helper routines to a different file
FDT helper file contain both fdt fixup and parsing functions.

Split the fixup related functions to a separate file for a better code
organization.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-03-24 13:30:32 +05:30