Commit 1c1c0003 authored by zhangtianyang's avatar zhangtianyang Committed by Hongchen Zhang
Browse files

Loongarch: Dynamic enable writecombine 

LoongArch inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/IAZ38J



--------------------------------

Signed-off-by: default avatarzhangtianyang <zhangtianyang@loongson.cn>
parent 375d7f74

arch/loongarch/kernel/setup.c

+26 −2
Original line number Diff line number Diff line
@@ -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();

}

include/drm/drm_cache.h

+1 −1
Original line number Diff line number Diff line
@@ -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