openwrt/target/linux/bcm53xx/patches-5.4/800-0001-firmware-bcm47xx_nvram-support-init-from-IO-memory.patch
Rafał Miłecki baf04eed02 bcm53xx: initialize NVRAM from NVMEM driver
NVRAM access may be needed early in boot process. Reading it using mtd
happens quite late in the init process. Add NVRAM initialization to the
NVMEM driver which comes up early and depends on IO mapping only.

This is required by Linksys devices which use NVRAM content for proper
partitioning (detecting current firmware partition).

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
2021-03-12 18:22:18 +01:00

62 lines
1.8 KiB
Diff

From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
Date: Thu, 11 Mar 2021 08:24:44 +0100
Subject: [PATCH] firmware: bcm47xx_nvram: support init from IO memory
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
drivers/firmware/broadcom/bcm47xx_nvram.c | 17 +++++++++++++++++
include/linux/bcm47xx_nvram.h | 6 ++++++
2 files changed, 23 insertions(+)
--- a/drivers/firmware/broadcom/bcm47xx_nvram.c
+++ b/drivers/firmware/broadcom/bcm47xx_nvram.c
@@ -110,6 +110,23 @@ found:
return 0;
}
+int bcm47xx_nvram_init_from_iomem(void __iomem *nvram_start, size_t res_size)
+{
+ if (nvram_len) {
+ pr_warn("nvram already initialized\n");
+ return -EEXIST;
+ }
+
+ if (!bcm47xx_nvram_is_valid(nvram_start)) {
+ pr_err("No valid NVRAM found\n");
+ return -ENOENT;
+ }
+
+ bcm47xx_nvram_copy(nvram_start, res_size);
+
+ return 0;
+}
+
/*
* On bcm47xx we need access to the NVRAM very early, so we can't use mtd
* subsystem to access flash. We can't even use platform device / driver to
--- a/include/linux/bcm47xx_nvram.h
+++ b/include/linux/bcm47xx_nvram.h
@@ -11,6 +11,7 @@
#include <linux/vmalloc.h>
#ifdef CONFIG_BCM47XX_NVRAM
+int bcm47xx_nvram_init_from_iomem(void __iomem *nvram_start, size_t res_size);
int bcm47xx_nvram_init_from_mem(u32 base, u32 lim);
int bcm47xx_nvram_getenv(const char *name, char *val, size_t val_len);
int bcm47xx_nvram_gpio_pin(const char *name);
@@ -20,6 +21,11 @@ static inline void bcm47xx_nvram_release
vfree(nvram);
};
#else
+static inline int bcm47xx_nvram_init_from_iomem(void __iomem *nvram_start,
+ size_t res_size)
+{
+ return -ENOTSUPP;
+}
static inline int bcm47xx_nvram_init_from_mem(u32 base, u32 lim)
{
return -ENOTSUPP;