On Thu, 2009-07-02 at 17:12 +0100, Martyn Welch wrote:
> Remove the reliance on a staticly defined NVRAM size, allowing platforms to
> support NVRAMs with sizes differing from the standard. A fall back value is
> provided for platforms not supporting this extension.
>
> Signed-off-by: Martyn Welch <martyn.we...@gefanuc.com>
What about other archs that use this driver ? They would also need
that new nvram_size() ...
BTW. This patch touches non-arch code so should at least be CCed to lkml
Cheers,
Ben.
> ---
>
> arch/powerpc/include/asm/nvram.h | 3 +++
> arch/powerpc/kernel/setup_32.c | 8 ++++++++
> drivers/char/generic_nvram.c | 27 ++++++++++++++++++++-------
> 3 files changed, 31 insertions(+), 7 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/nvram.h
> b/arch/powerpc/include/asm/nvram.h
> index efde5ac..71df8b2 100644
> --- a/arch/powerpc/include/asm/nvram.h
> +++ b/arch/powerpc/include/asm/nvram.h
> @@ -107,6 +107,9 @@ extern void pmac_xpram_write(int xpaddr, u8 data);
> /* Synchronize NVRAM */
> extern void nvram_sync(void);
>
> +/* Determine NVRAM size */
> +extern ssize_t nvram_size(void);
> +
> /* Normal access to NVRAM */
> extern unsigned char nvram_read_byte(int i);
> extern void nvram_write_byte(unsigned char c, int i);
> diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c
> index 1d15424..28f7570 100644
> --- a/arch/powerpc/kernel/setup_32.c
> +++ b/arch/powerpc/kernel/setup_32.c
> @@ -208,6 +208,14 @@ void nvram_write_byte(unsigned char val, int addr)
> }
> EXPORT_SYMBOL(nvram_write_byte);
>
> +ssize_t nvram_size(void)
> +{
> + if (ppc_md.nvram_size)
> + return ppc_md.nvram_size();
> + return -1;
> +}
> +EXPORT_SYMBOL(nvram_size);
> +
> void nvram_sync(void)
> {
> if (ppc_md.nvram_sync)
> diff --git a/drivers/char/generic_nvram.c b/drivers/char/generic_nvram.c
> index a00869c..e5f71f3 100644
> --- a/drivers/char/generic_nvram.c
> +++ b/drivers/char/generic_nvram.c
> @@ -2,7 +2,7 @@
> * Generic /dev/nvram driver for architectures providing some
> * "generic" hooks, that is :
> *
> - * nvram_read_byte, nvram_write_byte, nvram_sync
> + * nvram_read_byte, nvram_write_byte, nvram_sync, nvram_size
> *
> * Note that an additional hook is supported for PowerMac only
> * for getting the nvram "partition" informations
> @@ -28,6 +28,8 @@
>
> #define NVRAM_SIZE 8192
>
> +static ssize_t nvram_len;
> +
> static loff_t nvram_llseek(struct file *file, loff_t offset, int origin)
> {
> lock_kernel();
> @@ -36,7 +38,7 @@ static loff_t nvram_llseek(struct file *file, loff_t
> offset, int origin)
> offset += file->f_pos;
> break;
> case 2:
> - offset += NVRAM_SIZE;
> + offset += nvram_len;
> break;
> }
> if (offset < 0) {
> @@ -56,9 +58,9 @@ static ssize_t read_nvram(struct file *file, char __user
> *buf,
>
> if (!access_ok(VERIFY_WRITE, buf, count))
> return -EFAULT;
> - if (*ppos >= NVRAM_SIZE)
> + if (*ppos >= nvram_len)
> return 0;
> - for (i = *ppos; count > 0 && i < NVRAM_SIZE; ++i, ++p, --count)
> + for (i = *ppos; count > 0 && i < nvram_len; ++i, ++p, --count)
> if (__put_user(nvram_read_byte(i), p))
> return -EFAULT;
> *ppos = i;
> @@ -74,9 +76,9 @@ static ssize_t write_nvram(struct file *file, const char
> __user *buf,
>
> if (!access_ok(VERIFY_READ, buf, count))
> return -EFAULT;
> - if (*ppos >= NVRAM_SIZE)
> + if (*ppos >= nvram_len)
> return 0;
> - for (i = *ppos; count > 0 && i < NVRAM_SIZE; ++i, ++p, --count) {
> + for (i = *ppos; count > 0 && i < nvram_len; ++i, ++p, --count) {
> if (__get_user(c, p))
> return -EFAULT;
> nvram_write_byte(c, i);
> @@ -133,9 +135,20 @@ static struct miscdevice nvram_dev = {
>
> int __init nvram_init(void)
> {
> + int ret = 0;
> +
> printk(KERN_INFO "Generic non-volatile memory driver v%s\n",
> NVRAM_VERSION);
> - return misc_register(&nvram_dev);
> + ret = misc_register(&nvram_dev);
> + if (ret != 0)
> + goto out;
> +
> + nvram_len = nvram_size();
> + if (nvram_len < 0)
> + nvram_len = NVRAM_SIZE;
> +
> +out:
> + return ret;
> }
>
> void __exit nvram_cleanup(void)
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