- If Smepmp is enabled, the access flags of an entry are determined based on
  truth table defined in Smepmp.
- First PMP entry (index 0) is reserved.
- Existing boot PMP entries start from index 1.
- Since enabling Smepmp revokes the access privileges of the M-mode software
  on S/U-mode region, first PMP entry is used to map/unmap the shared memory
  between M and S/U-mode. This allows a temporary access window for the M-mode
  software to read/write to S/U-mode memory region.

Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

Configure PMP at last when all other initializations have been done.
Because if SMEPMP is detected, M-mode access to the S/U space will be
rescinded.

Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

Since pmp entries have implicit priority on index, previous entries will
deny access to SU on M-mode region. Also, M-mode will not have access to
SU region while previous entries will allow access to M-mode regions.

Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

- Add function to parse ISA string in FDT.
- Set Smepmp feature bit in extensions if "smepmp" string is found in ISA string.

Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

- Add Smepmp as extension in sbi_hart_extensions enum
- Return "smepmp" string for Smepmp extension from sbi_hart_extension_id2string

Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

Smepmp specification defines a truth table based on which the access is allowed to
different modes. This patch adds different flags based on this truth table.

Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

- Add a function to disable a given PMP entry.
- Add a function to check if a given entry is disabled.

Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

- Add macros for Machine Security Configuration (mseccfg) CSR
- Add macros to access/manipulate bits in msecfg CSR

Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

Currently, we see following compile error in the designeware GPIO driver
for RV32 systems:

lib/utils/gpio/fdt_gpio_designware.c:115:20: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
  115 |         chip->dr = (void *)addr + (bank * 0xc);
      |                    ^
lib/utils/gpio/fdt_gpio_designware.c:116:21: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
  116 |         chip->ext = (void *)addr + (bank * 4) + 0x50;

We fix the above error using an explicit type-cast to 'unsigned long'.

Fixes: 7828eeba

 ("gpio/desginware: add Synopsys DesignWare APB GPIO support")
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Xiang W <wxjstz@126.com>

Fix special case: sbi_snprintf(out, out_len, ...) when out_len equal
1, The previous code will not fill the buffer with any char.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

A single scan of the format char may add multiple characters to the
tbuf, causing a buffer overflow. You should check if tbuf is full in
printc so that it does not cause a buffer overflow.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

Because *out needs to reserve a byte to hold '\0', no more characters
should be added to the buffer when *out has one byte left, and the
buffer size *out_len should not be modified. this patch prevents
the correction of *out_len when *out_len is 1.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

When doing width = width - strlen(string) in prints there is no need
to consider the case that witdh may be less than 0. This is because
the code to do filling needs to be executed under the condition that
width > 0.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

Fix two bug:
> printf("%#08x", 0x123); /* print 0000x123 */
> printf("%#x", 0); /* print 0x0 */

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

Add o type for print to print octal numbers

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

The information of sg/b/letbase can be obtained by the type character,
simplifying the parameter by passing the type directly.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

The space flag is used to add a space before positive numbers, and
apostrophe is used to print the thousand separator. Add code to
ignore these two flags

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

Adds + flags for print, prefixing positive numbers with + when this
flags is present

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

Left alignment and padding '0' should not exist at the same time,
this patch skips padding.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

The flags for print should be able to appear in any order. The
previous code required the order to be fixed.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

Fix Priv spec version typo in commit d4b563c8 ("lib: sbi: Remove MCOUNTEREN
and SCOUNTEREN hart features").

At least Priv spec v1.11 is required for [m|s]counteren and mcountinhibit CSRs.

Fixes: d4b563c8

 ("lib: sbi: Remove MCOUNTEREN and SCOUNTEREN hart features")
Signed-off-by: Ley Foon Tan <leyfoon.tan@starfivetech.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

The hart_pmu_get_allowed_bits() function detects implemented bits
of mhpm counters so let us rename this function accordingly.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Xiang W <wxjstz@126.com>

Let us follow alphabetical order for HART ISA extension so that
it is simpler to maintain.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Xiang W <wxjstz@126.com>

Recently ratified Zihpm ISA extension covers all [m]hpm* CSRs
so we add Zihpm as a HART ISA extension in OpenSBI.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Xiang W <wxjstz@126.com>

Recently ratified Zicntr ISA extension covers cycle, time and
instret CSRs so we replace the "time" ISA extension with "zicntr"
ISA extension in OpenSBI.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Xiang W <wxjstz@126.com>

The cold_init() functions of ACLINT drivers should skip the HART
if sbi_hartid_to_scratch() returns NULL because we might be dealing
with a HART that is disabled in the device tree.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Xiang W <wxjstz@126.com>

Add a driver for the Synopsys DesignWare APB GPIO IP block found in many
SoCs.

Signed-off-by: Ben Dooks <ben.dooks@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

On a misconfigured system we could access phs->active_events[] out of
bounds. Check that num_hw_ctrs is less or equal SBI_PMU_HW_CTR_MAX.

Addresses-Coverity-ID: 1566113 ("Out-of-bounds read")
Addresses-Coverity-ID: 1566114 ("Out-of-bounds write")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

Use tabs rather than spaces.

Signed-off-by: Gianluca Guida <gianluca@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

This patch updates OpenSBI version to 1.3 as part of
release preparation.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>

Do not ignore register A2 (high bits of physical address) in the dbcn
handler (RV64).

Signed-off-by: Gianluca Guida <gianluca@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

The fdt_reset_thead driver needs to modify the __reset_thead_csr_stub
text region for the secondary harts booting. After that, the
sbi_hart_pmp_configure may lock down the text region with M_READABLE &
M_EXECUTABLE attributes in the future. Currently, the M_READABLE &
M_EXECUtABLE have no effect on m-mode, the L-bit in pmpcfg csr is
useless for the current opensbi scenario. See:

Priv-isa-spec 3.7.1.2. Locking and Privilege Mode
When the L bit is clear, any M-mode access matching the PMP entry will
succeed; the R/W/X permissions apply only to S and U modes.

That's why current fdt_reset_thead could still work well after commit:
230278dc ("lib: sbi: Add separate entries for firmware RX and RW
regions"). So this patch fixes up a fake bug for the M-mode permission
setting of the future.

Fixes: 230278dc ("lib: sbi: Add separate entries for firmware RX and RW regions")
Link: http://lists.infradead.org/pipermail/opensbi/2023-June/005176.html


Reported-by: Jessica Clarke <jrtc27@jrtc27.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Anup Patel <anup@brainfault.org>

After the loop to find the hartid is launched, assigning -1 to
index will fail in the subsequent compare instruction bge. Fix
This.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>

This reverts commit 6966ad0a ("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>

Over-time a lot of organizations and individuals have contributed to
the OpenSBI project so let us add copyright RISC-V International to
respect the contributions from all RISC-V members.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

We do have an official OpenSBI logo which was designed few months ago
and was also approved by RISC-V International. Lets add this logo
under docs and also use it in the top-level README.md

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

Instead of using a global array indexed by hartid, we should use
scratch space to save per-HART IMSIC pointer and IMSIC file number.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

The imsic_map_hartid_to_data() already checks hartid before using
so we don't need to check in imsic_update_hartid_table().

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

Instead of using a global array indexed by hartid, we should use
scratch space to save per-HART PLIC pointer and PLIC context numbers.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

Instead of using a global array indexed by hartid, we should use
scratch space to save per-HART MTIMER pointer.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>