| Message ID | 20090813075753.29726.28454.stgit@ES-J7S4D2J.amer.consind.ge.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
On Thu, 2009-08-13 at 09:03 +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.welch@gefanuc.com> > --- > > Ben: Is this a suitable solution? Yup. I'll have a closer look tomorrow. Thanks. Cheers, Ben. > v2: rename nvram_size() to nvram_get_size(), thus avoiding the collision with the global > variables in arch/powerpc/platforms/pseries/nvram.c and > arch/powerpc/platforms/chrp/nvram.c of the same name. > > 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..6c587ed 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_get_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 e1e3059..53bcf3d 100644 > --- a/arch/powerpc/kernel/setup_32.c > +++ b/arch/powerpc/kernel/setup_32.c > @@ -210,6 +210,14 @@ void nvram_write_byte(unsigned char val, int addr) > } > EXPORT_SYMBOL(nvram_write_byte); > > +ssize_t nvram_get_size(void) > +{ > + if (ppc_md.nvram_size) > + return ppc_md.nvram_size(); > + return -1; > +} > +EXPORT_SYMBOL(nvram_get_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..ef31738 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_get_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_get_size(); > + if (nvram_len < 0) > + nvram_len = NVRAM_SIZE; > + > +out: > + return ret; > } > > void __exit nvram_cleanup(void)
diff --git a/arch/powerpc/include/asm/nvram.h b/arch/powerpc/include/asm/nvram.h index efde5ac..6c587ed 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_get_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 e1e3059..53bcf3d 100644 --- a/arch/powerpc/kernel/setup_32.c +++ b/arch/powerpc/kernel/setup_32.c @@ -210,6 +210,14 @@ void nvram_write_byte(unsigned char val, int addr) } EXPORT_SYMBOL(nvram_write_byte); +ssize_t nvram_get_size(void) +{ + if (ppc_md.nvram_size) + return ppc_md.nvram_size(); + return -1; +} +EXPORT_SYMBOL(nvram_get_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..ef31738 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_get_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_get_size(); + if (nvram_len < 0) + nvram_len = NVRAM_SIZE; + +out: + return ret; } void __exit nvram_cleanup(void)
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.welch@gefanuc.com> --- Ben: Is this a suitable solution? v2: rename nvram_size() to nvram_get_size(), thus avoiding the collision with the global variables in arch/powerpc/platforms/pseries/nvram.c and arch/powerpc/platforms/chrp/nvram.c of the same name. 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(-)