From: zhangtianyang zhangtianyang@loongson.cn
LoongArch inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/IAZ38J
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Signed-off-by: zhangtianyang zhangtianyang@loongson.cn --- arch/loongarch/kernel/setup.c | 28 ++++++++++++++++++++++++++-- include/drm/drm_cache.h | 2 +- 2 files changed, 27 insertions(+), 3 deletions(-)
diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c index 481c85a5f1b5..a210e2507368 100644 --- a/arch/loongarch/kernel/setup.c +++ b/arch/loongarch/kernel/setup.c @@ -184,12 +184,14 @@ bool wc_enabled = false;
EXPORT_SYMBOL(wc_enabled);
+static int wc_arg = -1; + static int __init setup_writecombine(char *p) { if (!strcmp(p, "on")) - wc_enabled = true; + wc_arg = true; else if (!strcmp(p, "off")) - wc_enabled = false; + wc_arg = false; else pr_warn("Unknown writecombine setting "%s".\n", p);
@@ -371,6 +373,26 @@ static void __init bootcmdline_init(char **cmdline_p) *cmdline_p = boot_command_line; }
+static void __init writecombine_detect(void) +{ + u64 cpuname; + + if (wc_arg >= 0) { + wc_enabled = wc_arg; + return; + } + + cpuname = iocsr_read64(LOONGARCH_IOCSR_CPUNAME); + + switch (cpuname) { + case 0x0000303030364333: + wc_enabled = true; + break; + default: + break; + } +} + void __init platform_init(void) { arch_reserve_vmcore(); @@ -394,6 +416,8 @@ void __init platform_init(void) smbios_parse(); pr_info("The BIOS Version: %s\n", b_info.bios_version);
+ writecombine_detect(); + pr_info("WriteCombine: %s\n", wc_enabled ? "on":"off"); efi_runtime_init(); }
diff --git a/include/drm/drm_cache.h b/include/drm/drm_cache.h index 08e0e3ffad13..667fb0368ef6 100644 --- a/include/drm/drm_cache.h +++ b/include/drm/drm_cache.h @@ -74,7 +74,7 @@ static inline bool drm_arch_can_wc_memory(void) * cache coherency machanism. This means WUC can only used for write-only * memory regions. */ - return false; + return wc_enabled; #else return true; #endif