From 496ea826d1e1f9744e2a4c36043db933deebab43 Mon Sep 17 00:00:00 2001 From: Conor Dooley Date: Thu, 13 Jul 2023 13:11:09 +0100 Subject: RISC-V: provide Kconfig & commandline options to control parsing "riscv,isa" As it says on the tin, provide Kconfig option to control parsing the "riscv,isa" devicetree property. If either option is used, the kernel will fall back to parsing "riscv,isa", where "riscv,isa-base" and "riscv,isa-extensions" are not present. The Kconfig options are set up so that the default kernel configuration will enable the fallback path, without needing the commandline option. Suggested-by: Andrew Jones Suggested-by: Palmer Dabbelt Reviewed-by: Andrew Jones Signed-off-by: Conor Dooley Link: https://lore.kernel.org/r/20230713-aviator-plausibly-a35662485c2c@wendy Signed-off-by: Palmer Dabbelt --- Documentation/admin-guide/kernel-parameters.txt | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'Documentation/admin-guide/kernel-parameters.txt') diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a1457995fd41..bdc3fa712e92 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5468,6 +5468,13 @@ [KNL] Disable ring 3 MONITOR/MWAIT feature on supported CPUs. + riscv_isa_fallback [RISCV] + When CONFIG_RISCV_ISA_FALLBACK is not enabled, permit + falling back to detecting extension support by parsing + "riscv,isa" property on devicetree systems when the + replacement properties are not found. See the Kconfig + entry for RISCV_ISA_FALLBACK. + ro [KNL] Mount root device read-only on boot rodata= [KNL] -- cgit From 33f0dd973d4e7d3ed208b5df027490380d5876ab Mon Sep 17 00:00:00 2001 From: Chen Jiahao Date: Wed, 26 Jul 2023 17:50:00 +0000 Subject: docs: kdump: Update the crashkernel description for riscv Now "crashkernel=" parameter on riscv has been updated to support crashkernel=X,[high,low]. Through which we can reserve memory region above/within 32bit addressible DMA zone. Here update the parameter description accordingly. Signed-off-by: Chen Jiahao Reviewed-by: Guo Ren Reviewed-by: Simon Horman Reviewed-by: Zhen Lei Acked-by: Baoquan He Link: https://lore.kernel.org/r/20230726175000.2536220-3-chenjiahao16@huawei.com Signed-off-by: Palmer Dabbelt --- Documentation/admin-guide/kernel-parameters.txt | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) (limited to 'Documentation/admin-guide/kernel-parameters.txt') diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a1457995fd41..bd519749968f 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -862,7 +862,7 @@ memory region [offset, offset + size] for that kernel image. If '@offset' is omitted, then a suitable offset is selected automatically. - [KNL, X86-64, ARM64] Select a region under 4G first, and + [KNL, X86-64, ARM64, RISCV] Select a region under 4G first, and fall back to reserve region above 4G when '@offset' hasn't been specified. See Documentation/admin-guide/kdump/kdump.rst for further details. @@ -875,14 +875,14 @@ Documentation/admin-guide/kdump/kdump.rst for an example. crashkernel=size[KMG],high - [KNL, X86-64, ARM64] range could be above 4G. Allow kernel - to allocate physical memory region from top, so could - be above 4G if system have more than 4G ram installed. - Otherwise memory region will be allocated below 4G, if - available. + [KNL, X86-64, ARM64, RISCV] range could be above 4G. + Allow kernel to allocate physical memory region from top, + so could be above 4G if system have more than 4G ram + installed. Otherwise memory region will be allocated + below 4G, if available. It will be ignored if crashkernel=X is specified. crashkernel=size[KMG],low - [KNL, X86-64, ARM64] range under 4G. When crashkernel=X,high + [KNL, X86-64, ARM64, RISCV] range under 4G. When crashkernel=X,high is passed, kernel could allocate physical memory region above 4G, that cause second kernel crash on system that require some amount of low memory, e.g. swiotlb @@ -893,6 +893,7 @@ size is platform dependent. --> x86: max(swiotlb_size_or_default() + 8MiB, 256MiB) --> arm64: 128MiB + --> riscv: 128MiB This one lets the user specify own low range under 4G for second kernel instead. 0: to disable low allocation. -- cgit