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-rw-r--r--Documentation/arch/riscv/hwprobe.rst122
1 files changed, 115 insertions, 7 deletions
diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst
index 7b2384de47..b2bcc9eed9 100644
--- a/Documentation/arch/riscv/hwprobe.rst
+++ b/Documentation/arch/riscv/hwprobe.rst
@@ -12,7 +12,7 @@ is defined in <asm/hwprobe.h>::
};
long sys_riscv_hwprobe(struct riscv_hwprobe *pairs, size_t pair_count,
- size_t cpu_count, cpu_set_t *cpus,
+ size_t cpusetsize, cpu_set_t *cpus,
unsigned int flags);
The arguments are split into three groups: an array of key-value pairs, a CPU
@@ -20,12 +20,26 @@ set, and some flags. The key-value pairs are supplied with a count. Userspace
must prepopulate the key field for each element, and the kernel will fill in the
value if the key is recognized. If a key is unknown to the kernel, its key field
will be cleared to -1, and its value set to 0. The CPU set is defined by
-CPU_SET(3). For value-like keys (eg. vendor/arch/impl), the returned value will
-be only be valid if all CPUs in the given set have the same value. Otherwise -1
-will be returned. For boolean-like keys, the value returned will be a logical
-AND of the values for the specified CPUs. Usermode can supply NULL for cpus and
-0 for cpu_count as a shortcut for all online CPUs. There are currently no flags,
-this value must be zero for future compatibility.
+CPU_SET(3) with size ``cpusetsize`` bytes. For value-like keys (eg. vendor,
+arch, impl), the returned value will only be valid if all CPUs in the given set
+have the same value. Otherwise -1 will be returned. For boolean-like keys, the
+value returned will be a logical AND of the values for the specified CPUs.
+Usermode can supply NULL for ``cpus`` and 0 for ``cpusetsize`` as a shortcut for
+all online CPUs. The currently supported flags are:
+
+* :c:macro:`RISCV_HWPROBE_WHICH_CPUS`: This flag basically reverses the behavior
+ of sys_riscv_hwprobe(). Instead of populating the values of keys for a given
+ set of CPUs, the values of each key are given and the set of CPUs is reduced
+ by sys_riscv_hwprobe() to only those which match each of the key-value pairs.
+ How matching is done depends on the key type. For value-like keys, matching
+ means to be the exact same as the value. For boolean-like keys, matching
+ means the result of a logical AND of the pair's value with the CPU's value is
+ exactly the same as the pair's value. Additionally, when ``cpus`` is an empty
+ set, then it is initialized to all online CPUs which fit within it, i.e. the
+ CPU set returned is the reduction of all the online CPUs which can be
+ represented with a CPU set of size ``cpusetsize``.
+
+All other flags are reserved for future compatibility and must be zero.
On success 0 is returned, on failure a negative error code is returned.
@@ -80,6 +94,100 @@ The following keys are defined:
* :c:macro:`RISCV_HWPROBE_EXT_ZICBOZ`: The Zicboz extension is supported, as
ratified in commit 3dd606f ("Create cmobase-v1.0.pdf") of riscv-CMOs.
+ * :c:macro:`RISCV_HWPROBE_EXT_ZBC` The Zbc extension is supported, as defined
+ in version 1.0 of the Bit-Manipulation ISA extensions.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZBKB` The Zbkb extension is supported, as
+ defined in version 1.0 of the Scalar Crypto ISA extensions.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZBKC` The Zbkc extension is supported, as
+ defined in version 1.0 of the Scalar Crypto ISA extensions.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZBKX` The Zbkx extension is supported, as
+ defined in version 1.0 of the Scalar Crypto ISA extensions.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZKND` The Zknd extension is supported, as
+ defined in version 1.0 of the Scalar Crypto ISA extensions.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZKNE` The Zkne extension is supported, as
+ defined in version 1.0 of the Scalar Crypto ISA extensions.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZKNH` The Zknh extension is supported, as
+ defined in version 1.0 of the Scalar Crypto ISA extensions.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZKSED` The Zksed extension is supported, as
+ defined in version 1.0 of the Scalar Crypto ISA extensions.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZKSH` The Zksh extension is supported, as
+ defined in version 1.0 of the Scalar Crypto ISA extensions.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZKT` The Zkt extension is supported, as defined
+ in version 1.0 of the Scalar Crypto ISA extensions.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVBB`: The Zvbb extension is supported as
+ defined in version 1.0 of the RISC-V Cryptography Extensions Volume II.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVBC`: The Zvbc extension is supported as
+ defined in version 1.0 of the RISC-V Cryptography Extensions Volume II.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVKB`: The Zvkb extension is supported as
+ defined in version 1.0 of the RISC-V Cryptography Extensions Volume II.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVKG`: The Zvkg extension is supported as
+ defined in version 1.0 of the RISC-V Cryptography Extensions Volume II.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVKNED`: The Zvkned extension is supported as
+ defined in version 1.0 of the RISC-V Cryptography Extensions Volume II.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVKNHA`: The Zvknha extension is supported as
+ defined in version 1.0 of the RISC-V Cryptography Extensions Volume II.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVKNHB`: The Zvknhb extension is supported as
+ defined in version 1.0 of the RISC-V Cryptography Extensions Volume II.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVKSED`: The Zvksed extension is supported as
+ defined in version 1.0 of the RISC-V Cryptography Extensions Volume II.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVKSH`: The Zvksh extension is supported as
+ defined in version 1.0 of the RISC-V Cryptography Extensions Volume II.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVKT`: The Zvkt extension is supported as
+ defined in version 1.0 of the RISC-V Cryptography Extensions Volume II.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZFH`: The Zfh extension version 1.0 is supported
+ as defined in the RISC-V ISA manual.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZFHMIN`: The Zfhmin extension version 1.0 is
+ supported as defined in the RISC-V ISA manual.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZIHINTNTL`: The Zihintntl extension version 1.0
+ is supported as defined in the RISC-V ISA manual.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVFH`: The Zvfh extension is supported as
+ defined in the RISC-V Vector manual starting from commit e2ccd0548d6c
+ ("Remove draft warnings from Zvfh[min]").
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVFHMIN`: The Zvfhmin extension is supported as
+ defined in the RISC-V Vector manual starting from commit e2ccd0548d6c
+ ("Remove draft warnings from Zvfh[min]").
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZFA`: The Zfa extension is supported as
+ defined in the RISC-V ISA manual starting from commit 056b6ff467c7
+ ("Zfa is ratified").
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZTSO`: The Ztso extension is supported as
+ defined in the RISC-V ISA manual starting from commit 5618fb5a216b
+ ("Ztso is now ratified.")
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZACAS`: The Zacas extension is supported as
+ defined in the Atomic Compare-and-Swap (CAS) instructions manual starting
+ from commit 5059e0ca641c ("update to ratified").
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZICOND`: The Zicond extension is supported as
+ defined in the RISC-V Integer Conditional (Zicond) operations extension
+ manual starting from commit 95cf1f9 ("Add changes requested by Ved
+ during signoff")
+
* :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: A bitmask that contains performance
information about the selected set of processors.