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authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /drivers/acpi/riscv/cppc.c
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip
ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with: Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301: ERROR: Unexpected indentation. [docutils] The Return: section of ata_dsm_trim_pages() ends its first sentence with a colon and continues with an indented bullet list. reStructuredText requires a blank line before an indented block, so docutils chokes on the list. Simply adding the missing blank line does not work either: Return: is a kernel-doc "special section", which is terminated by the first blank line, so the bullet list would end up in the Description section, detached from the sentence introducing it. Spell the two bounds out as prose instead, so that the Return: section stays self-contained. Documentation-only change. Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND") Reported-by: Thomas Huth <thuth@redhat.com> Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'drivers/acpi/riscv/cppc.c')
-rw-r--r--drivers/acpi/riscv/cppc.c155
1 files changed, 155 insertions, 0 deletions
diff --git a/drivers/acpi/riscv/cppc.c b/drivers/acpi/riscv/cppc.c
new file mode 100644
index 000000000..42c1a9052
--- /dev/null
+++ b/drivers/acpi/riscv/cppc.c
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Implement CPPC FFH helper routines for RISC-V.
+ *
+ * Copyright (C) 2024 Ventana Micro Systems Inc.
+ */
+
+#include <acpi/cppc_acpi.h>
+#include <asm/csr.h>
+#include <asm/sbi.h>
+
+#define SBI_EXT_CPPC 0x43505043
+
+/* CPPC interfaces defined in SBI spec */
+#define SBI_CPPC_PROBE 0x0
+#define SBI_CPPC_READ 0x1
+#define SBI_CPPC_READ_HI 0x2
+#define SBI_CPPC_WRITE 0x3
+
+/* RISC-V FFH definitions from RISC-V FFH spec */
+#define FFH_CPPC_TYPE(r) (((r) & GENMASK_ULL(63, 60)) >> 60)
+#define FFH_CPPC_SBI_REG(r) ((r) & GENMASK(31, 0))
+#define FFH_CPPC_CSR_NUM(r) ((r) & GENMASK(11, 0))
+
+#define FFH_CPPC_SBI 0x1
+#define FFH_CPPC_CSR 0x2
+
+struct sbi_cppc_data {
+ u64 val;
+ u32 reg;
+ struct sbiret ret;
+};
+
+static bool cppc_ext_present;
+
+static int __init sbi_cppc_init(void)
+{
+ if (sbi_spec_version >= sbi_mk_version(2, 0) &&
+ sbi_probe_extension(SBI_EXT_CPPC) > 0) {
+ cppc_ext_present = true;
+ } else {
+ cppc_ext_present = false;
+ }
+
+ return 0;
+}
+device_initcall(sbi_cppc_init);
+
+static void sbi_cppc_read(void *read_data)
+{
+ struct sbi_cppc_data *data = (struct sbi_cppc_data *)read_data;
+
+ data->ret = sbi_ecall(SBI_EXT_CPPC, SBI_CPPC_READ,
+ data->reg, 0, 0, 0, 0, 0);
+}
+
+static void sbi_cppc_write(void *write_data)
+{
+ struct sbi_cppc_data *data = (struct sbi_cppc_data *)write_data;
+
+ data->ret = sbi_ecall(SBI_EXT_CPPC, SBI_CPPC_WRITE,
+ data->reg, data->val, 0, 0, 0, 0);
+}
+
+static void cppc_ffh_csr_read(void *read_data)
+{
+ struct sbi_cppc_data *data = (struct sbi_cppc_data *)read_data;
+
+ switch (data->reg) {
+ /* Support only TIME CSR for now */
+ case CSR_TIME:
+ data->ret.value = csr_read(CSR_TIME);
+ data->ret.error = 0;
+ break;
+ default:
+ data->ret.error = -EINVAL;
+ break;
+ }
+}
+
+static void cppc_ffh_csr_write(void *write_data)
+{
+ struct sbi_cppc_data *data = (struct sbi_cppc_data *)write_data;
+
+ data->ret.error = -EINVAL;
+}
+
+/*
+ * Refer to drivers/acpi/cppc_acpi.c for the description of the functions
+ * below.
+ */
+bool cpc_ffh_supported(void)
+{
+ return true;
+}
+
+int cpc_read_ffh(int cpu, struct cpc_reg *reg, u64 *val)
+{
+ struct sbi_cppc_data data;
+
+ if (WARN_ON_ONCE(irqs_disabled()))
+ return -EPERM;
+
+ if (FFH_CPPC_TYPE(reg->address) == FFH_CPPC_SBI) {
+ if (!cppc_ext_present)
+ return -EINVAL;
+
+ data.reg = FFH_CPPC_SBI_REG(reg->address);
+
+ smp_call_function_single(cpu, sbi_cppc_read, &data, 1);
+
+ *val = data.ret.value;
+
+ return (data.ret.error) ? sbi_err_map_linux_errno(data.ret.error) : 0;
+ } else if (FFH_CPPC_TYPE(reg->address) == FFH_CPPC_CSR) {
+ data.reg = FFH_CPPC_CSR_NUM(reg->address);
+
+ smp_call_function_single(cpu, cppc_ffh_csr_read, &data, 1);
+
+ *val = data.ret.value;
+
+ return data.ret.error;
+ }
+
+ return -EINVAL;
+}
+
+int cpc_write_ffh(int cpu, struct cpc_reg *reg, u64 val)
+{
+ struct sbi_cppc_data data;
+
+ if (WARN_ON_ONCE(irqs_disabled()))
+ return -EPERM;
+
+ if (FFH_CPPC_TYPE(reg->address) == FFH_CPPC_SBI) {
+ if (!cppc_ext_present)
+ return -EINVAL;
+
+ data.reg = FFH_CPPC_SBI_REG(reg->address);
+ data.val = val;
+
+ smp_call_function_single(cpu, sbi_cppc_write, &data, 1);
+
+ return (data.ret.error) ? sbi_err_map_linux_errno(data.ret.error) : 0;
+ } else if (FFH_CPPC_TYPE(reg->address) == FFH_CPPC_CSR) {
+ data.reg = FFH_CPPC_CSR_NUM(reg->address);
+ data.val = val;
+
+ smp_call_function_single(cpu, cppc_ffh_csr_write, &data, 1);
+
+ return data.ret.error;
+ }
+
+ return -EINVAL;
+}