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authorLinus Torvalds <torvalds@linux-foundation.org>2023-09-10 00:25:11 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2023-09-10 00:25:11 +0300
commit1b37a0a2d46f0c5fa5eee170ddeeb83342faa117 (patch)
tree162022b849419b0f3606c0388f6dc15e4e0925e5 /arch/riscv/errata/andes/errata.c
parent2a5a4326e58339a26cd1510259e7310b8c0980ff (diff)
parentc6a906cce61a8015b622707f9c12003f90673399 (diff)
downloadlinux-1b37a0a2d46f0c5fa5eee170ddeeb83342faa117.tar.xz
Merge tag 'riscv-for-linus-6.6-mw2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull more RISC-V updates from Palmer Dabbelt: - The kernel now dynamically probes for misaligned access speed, as opposed to relying on a table of known implementations. - Support for non-coherent devices on systems using the Andes AX45MP core, including the RZ/Five SoCs. - Support for the V extension in ptrace(), again. - Support for KASLR. - Support for the BPF prog pack allocator in RISC-V. - A handful of bug fixes and cleanups. * tag 'riscv-for-linus-6.6-mw2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (25 commits) soc: renesas: Kconfig: For ARCH_R9A07G043 select the required configs if dependencies are met riscv: Kconfig.errata: Add dependency for RISCV_SBI in ERRATA_ANDES config riscv: Kconfig.errata: Drop dependency for MMU in ERRATA_ANDES_CMO config riscv: Kconfig: Select DMA_DIRECT_REMAP only if MMU is enabled bpf, riscv: use prog pack allocator in the BPF JIT riscv: implement a memset like function for text riscv: extend patch_text_nosync() for multiple pages bpf: make bpf_prog_pack allocator portable riscv: libstub: Implement KASLR by using generic functions libstub: Fix compilation warning for rv32 arm64: libstub: Move KASLR handling functions to kaslr.c riscv: Dump out kernel offset information on panic riscv: Introduce virtual kernel mapping KASLR RISC-V: Add ptrace support for vectors soc: renesas: Kconfig: Select the required configs for RZ/Five SoC cache: Add L2 cache management for Andes AX45MP RISC-V core dt-bindings: cache: andestech,ax45mp-cache: Add DT binding documentation for L2 cache controller riscv: mm: dma-noncoherent: nonstandard cache operations support riscv: errata: Add Andes alternative ports riscv: asm: vendorid_list: Add Andes Technology to the vendors list ...
Diffstat (limited to 'arch/riscv/errata/andes/errata.c')
-rw-r--r--arch/riscv/errata/andes/errata.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/arch/riscv/errata/andes/errata.c b/arch/riscv/errata/andes/errata.c
new file mode 100644
index 000000000000..197db68cc8da
--- /dev/null
+++ b/arch/riscv/errata/andes/errata.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Erratas to be applied for Andes CPU cores
+ *
+ * Copyright (C) 2023 Renesas Electronics Corporation.
+ *
+ * Author: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
+ */
+
+#include <linux/memory.h>
+#include <linux/module.h>
+
+#include <asm/alternative.h>
+#include <asm/cacheflush.h>
+#include <asm/errata_list.h>
+#include <asm/patch.h>
+#include <asm/processor.h>
+#include <asm/sbi.h>
+#include <asm/vendorid_list.h>
+
+#define ANDESTECH_AX45MP_MARCHID 0x8000000000008a45UL
+#define ANDESTECH_AX45MP_MIMPID 0x500UL
+#define ANDESTECH_SBI_EXT_ANDES 0x0900031E
+
+#define ANDES_SBI_EXT_IOCP_SW_WORKAROUND 1
+
+static long ax45mp_iocp_sw_workaround(void)
+{
+ struct sbiret ret;
+
+ /*
+ * ANDES_SBI_EXT_IOCP_SW_WORKAROUND SBI EXT checks if the IOCP is missing and
+ * cache is controllable only then CMO will be applied to the platform.
+ */
+ ret = sbi_ecall(ANDESTECH_SBI_EXT_ANDES, ANDES_SBI_EXT_IOCP_SW_WORKAROUND,
+ 0, 0, 0, 0, 0, 0);
+
+ return ret.error ? 0 : ret.value;
+}
+
+static bool errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
+{
+ if (!IS_ENABLED(CONFIG_ERRATA_ANDES_CMO))
+ return false;
+
+ if (arch_id != ANDESTECH_AX45MP_MARCHID || impid != ANDESTECH_AX45MP_MIMPID)
+ return false;
+
+ if (!ax45mp_iocp_sw_workaround())
+ return false;
+
+ /* Set this just to make core cbo code happy */
+ riscv_cbom_block_size = 1;
+ riscv_noncoherent_supported();
+
+ return true;
+}
+
+void __init_or_module andes_errata_patch_func(struct alt_entry *begin, struct alt_entry *end,
+ unsigned long archid, unsigned long impid,
+ unsigned int stage)
+{
+ errata_probe_iocp(stage, archid, impid);
+
+ /* we have nothing to patch here ATM so just return back */
+}