lkml.org 
[lkml]   [2022]   [Aug]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3/4] RISC-V: Implement arch specific PMEM APIs
Date
The NVDIMM PMEM driver expects arch specific APIs for cache maintenance
and if arch does not provide these APIs then NVDIMM PMEM driver will
always use MEMREMAP_WT to map persistent memory which in-turn maps as
UC memory type defined by the RISC-V Svpbmt specification.

Now that the Svpbmt and Zicbom support is available in RISC-V kernel,
we implement PMEM APIs using ALT_CMO_OP() macros so that the NVDIMM
PMEM driver can use MEMREMAP_WB to map persistent memory.

Co-developed-by: Mayuresh Chitale <mchitale@ventanamicro.com>
Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
arch/riscv/Kconfig | 1 +
arch/riscv/mm/Makefile | 1 +
arch/riscv/mm/pmem.c | 21 +++++++++++++++++++++
3 files changed, 23 insertions(+)
create mode 100644 arch/riscv/mm/pmem.c

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 0ebd8da388d8..37d6370d29c3 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -25,6 +25,7 @@ config RISCV
select ARCH_HAS_GIGANTIC_PAGE
select ARCH_HAS_KCOV
select ARCH_HAS_MMIOWB
+ select ARCH_HAS_PMEM_API
select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_SET_DIRECT_MAP if MMU
select ARCH_HAS_SET_MEMORY if MMU
diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile
index d76aabf4b94d..3b368e547f83 100644
--- a/arch/riscv/mm/Makefile
+++ b/arch/riscv/mm/Makefile
@@ -31,3 +31,4 @@ endif

obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o
obj-$(CONFIG_RISCV_DMA_NONCOHERENT) += dma-noncoherent.o
+obj-$(CONFIG_ARCH_HAS_PMEM_API) += pmem.o
diff --git a/arch/riscv/mm/pmem.c b/arch/riscv/mm/pmem.c
new file mode 100644
index 000000000000..089df92ae876
--- /dev/null
+++ b/arch/riscv/mm/pmem.c
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022 Ventana Micro Systems Inc.
+ */
+
+#include <linux/export.h>
+#include <linux/libnvdimm.h>
+
+#include <asm/cacheflush.h>
+
+void arch_wb_cache_pmem(void *addr, size_t size)
+{
+ ALT_CMO_OP(clean, addr, size, riscv_cbom_block_size);
+}
+EXPORT_SYMBOL_GPL(arch_wb_cache_pmem);
+
+void arch_invalidate_pmem(void *addr, size_t size)
+{
+ ALT_CMO_OP(inval, addr, size, riscv_cbom_block_size);
+}
+EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
--
2.34.1
\
 
 \ /
  Last update: 2022-08-29 15:03    [W:1.583 / U:0.004 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site