rvc/linux-_pi_-patches-for-rvc.patch

From 30022eebb78abc5a8a9289aecbd30a155fafcff0 Mon Sep 17 00:00:00 2001
From: Stefan <stefan@pimaker.at>
Date: Sun, 1 Aug 2021 20:58:20 +0200
Subject: [PATCH] _pi_ patches for rvc

* use MEMOP extension for faster memcpy
* don't poison init kernel area, we don't care about security
* print more messages about initramfs loading, since otherwise it just
  looks like it got stuck

Signed-off-by: Stefan <stefan@pimaker.at>
---
 arch/riscv/lib/memcpy.S | 14 ++++++++++++++
 include/linux/mm.h      |  2 +-
 init/initramfs.c        | 19 +++++++++++++++++--
 3 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/arch/riscv/lib/memcpy.S b/arch/riscv/lib/memcpy.S
index 51ab716253fa..67e3cf24d9d0 100644
--- a/arch/riscv/lib/memcpy.S
+++ b/arch/riscv/lib/memcpy.S
@@ -41,6 +41,19 @@ WEAK(memcpy)
 	beqz a4, 4f
 	add a3, a1, a4
 3:
+	# fast memcpy for page-sized chunks
+	lla t0, 10f
+	li t2, 4096
+	bne a2, t2, 11f
+
+	csrw 0x0b1, a1 # src
+	csrw 0x0b2, t6 # dst
+	csrw 0x0b3, a2 # n
+	li t2, 0x1
+	csrw 0x0b0, t2 # memcpy
+	j 10f
+
+11:
 	REG_L a4,       0(a1)
 	REG_L a5,   SZREG(a1)
 	REG_L a6, 2*SZREG(a1)
@@ -76,6 +89,7 @@ WEAK(memcpy)
 	REG_S t1, 15*SZREG(t6)
 	addi t6, t6, 16*SZREG
 	bltu a1, a3, 3b
+10:
 	andi a2, a2, (16*SZREG)-1  /* Update count */
 
 4:
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 9afb8998e7e5..881f1c1cf7ea 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2420,7 +2420,7 @@ static inline unsigned long free_initmem_default(int poison)
 	extern char __init_begin[], __init_end[];
 
 	return free_reserved_area(&__init_begin, &__init_end,
-				  poison, "unused kernel");
+				  0x1ff, "unused kernel");
 }
 
 static inline unsigned long get_num_physpages(void)
diff --git a/init/initramfs.c b/init/initramfs.c
index af27abc59643..1124f0cf6c8f 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -43,8 +43,10 @@ static ssize_t __init xwrite(struct file *file, const char *p, size_t count,
 static __initdata char *message;
 static void __init error(char *x)
 {
-	if (!message)
+	if (!message) {
 		message = x;
+		pr_err("[_pi_] initramfs error: %s\n", x);
+	}
 }
 
 static void panic_show_mem(const char *fmt, ...)
@@ -467,6 +469,9 @@ static char * __init unpack_to_rootfs(char *buf, unsigned long len)
 	const char *compress_name;
 	static __initdata char msg_buf[64];
 
+	unsigned long len_orig = len;
+	unsigned long len_percent = 0, len_percent_tmp;
+
 	header_buf = kmalloc(110, GFP_KERNEL);
 	symlink_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, GFP_KERNEL);
 	name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL);
@@ -474,11 +479,20 @@ static char * __init unpack_to_rootfs(char *buf, unsigned long len)
 	if (!header_buf || !symlink_buf || !name_buf)
 		panic_show_mem("can't allocate buffers");
 
+	pr_info("[_pi_] loading initramfs now, this may take a while...\n");
+
 	state = Start;
 	this_header = 0;
 	message = NULL;
 	while (!message && len) {
 		loff_t saved_offset = this_header;
+
+		len_percent_tmp = (len * 10) / len_orig;
+		if (len_percent_tmp != len_percent) {
+			len_percent = len_percent_tmp;
+			pr_info("[_pi_] initramfs: %lu0%% done\n", 10 - len_percent);
+		}
+
 		if (*buf == '0' && !(this_header & 3)) {
 			state = Start;
 			written = write_buffer(buf, len);
@@ -494,7 +508,7 @@ static char * __init unpack_to_rootfs(char *buf, unsigned long len)
 		}
 		this_header = 0;
 		decompress = decompress_method(buf, len, &compress_name);
-		pr_debug("Detected %s compressed data\n", compress_name);
+		pr_info("Detected %s compressed data\n", compress_name);
 		if (decompress) {
 			int res = decompress(buf, len, NULL, flush_buffer, NULL,
 				   &my_inptr, error);
@@ -519,6 +533,7 @@ static char * __init unpack_to_rootfs(char *buf, unsigned long len)
 	kfree(name_buf);
 	kfree(symlink_buf);
 	kfree(header_buf);
+	pr_info("[_pi_] unpack_to_rootfs retval: %s\n", (message && *message) ? message : "<success>");
 	return message;
 }
 
-- 
2.32.0