mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-21 06:33:41 +00:00
793f8ab62c
Add kernel patches for version 6.1. Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
67 lines
2.0 KiB
Diff
67 lines
2.0 KiB
Diff
From 3537a855e3858b1f8b6cee545a22b8b67037235c Mon Sep 17 00:00:00 2001
|
|
From: Phil Elwell <phil@raspberrypi.com>
|
|
Date: Wed, 22 Mar 2023 15:30:38 +0000
|
|
Subject: [PATCH] hwrng: bcm2835 - sleep more intelligently
|
|
|
|
While waiting for random data, use sleeps that are proportional
|
|
to the amount of data expected. Prevent indefinite waits by
|
|
giving up if nothing is received for a second.
|
|
|
|
See: https://github.com/raspberrypi/linux/issues/5390
|
|
|
|
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
|
|
---
|
|
drivers/char/hw_random/bcm2835-rng.c | 20 ++++++++++++++------
|
|
1 file changed, 14 insertions(+), 6 deletions(-)
|
|
|
|
--- a/drivers/char/hw_random/bcm2835-rng.c
|
|
+++ b/drivers/char/hw_random/bcm2835-rng.c
|
|
@@ -14,6 +14,7 @@
|
|
#include <linux/printk.h>
|
|
#include <linux/clk.h>
|
|
#include <linux/reset.h>
|
|
+#include <linux/delay.h>
|
|
|
|
#define RNG_CTRL 0x0
|
|
#define RNG_STATUS 0x4
|
|
@@ -28,6 +29,9 @@
|
|
|
|
#define RNG_INT_OFF 0x1
|
|
|
|
+#define RNG_FIFO_WORDS 4
|
|
+#define RNG_US_PER_WORD 34 /* Tuned for throughput */
|
|
+
|
|
struct bcm2835_rng_priv {
|
|
struct hwrng rng;
|
|
void __iomem *base;
|
|
@@ -64,19 +68,23 @@ static inline void rng_writel(struct bcm
|
|
static int bcm2835_rng_read(struct hwrng *rng, void *buf, size_t max,
|
|
bool wait)
|
|
{
|
|
+ u32 retries = 1000000/(RNG_FIFO_WORDS * RNG_US_PER_WORD);
|
|
struct bcm2835_rng_priv *priv = to_rng_priv(rng);
|
|
u32 max_words = max / sizeof(u32);
|
|
u32 num_words, count;
|
|
|
|
- while ((rng_readl(priv, RNG_STATUS) >> 24) == 0) {
|
|
- if (!wait)
|
|
+ num_words = rng_readl(priv, RNG_STATUS) >> 24;
|
|
+
|
|
+ while (!num_words) {
|
|
+ if (!wait || !retries)
|
|
return 0;
|
|
- hwrng_msleep(rng, 1000);
|
|
+ retries--;
|
|
+ usleep_range((u32)RNG_US_PER_WORD,
|
|
+ (u32)RNG_US_PER_WORD * RNG_FIFO_WORDS);
|
|
+ num_words = rng_readl(priv, RNG_STATUS) >> 24;
|
|
}
|
|
|
|
- num_words = rng_readl(priv, RNG_STATUS) >> 24;
|
|
- if (num_words > max_words)
|
|
- num_words = max_words;
|
|
+ num_words = min(num_words, max_words);
|
|
|
|
for (count = 0; count < num_words; count++)
|
|
((u32 *)buf)[count] = rng_readl(priv, RNG_DATA);
|