Re: [PATCH RESEND] ARM: dts: keystone-k2*: Increase SPI Flash partition size for U-Boot
On Wednesday 12 October 2016 05:27 PM, Russell King - ARM Linux wrote: > On Wed, Oct 12, 2016 at 04:30:28PM +0530, Vignesh R wrote: [...] >>> >>> - What is this "misc" partition? >>> >> >> This partition seems to exists from the very beginning. I believe, this >> is just a spare area of flash that can be used as per end-user >> requirement. Either to store a small filesystem or kernel. Copying >> Murali who added above partition if he has any input here. >> >>> - Why is it safe to move the "misc" partition in this way? >>> >>> - Do users need to do anything with data stored in the "misc" partition >>> when changing kernels? >>> >> >> MTD layer will take care of most abstractions (like start address etc). >> Will add a note in commit message informing about the reduction in size >> of the partition. >> >>> If the "misc" partition is simply unused space on the flash device, why >>> list it in DT? >>> >> >> If the unused space is not listed in the DT, then there is no /dev/mtdX >> node created for the unused section. User will then have to manually >> edit DT, in order to get the node and mount it. Instead, lets make it >> available by default. > > So, taken all together, your argument is: > > - We want a user partition > - It's okay to destroy the data in the user's partition by moving it > around randomly between kernel versions. > > The two do not naturally go together at all. You're messing with user > expectations in ways you should not be. This really is not an acceptable > approach. > Ok, I understand that if the user just updates to new kernel(w/o updating bootloader) then this patch will end up setting "misc" partition at wrong offset. At this point, I don't see how to provide a way to upgrade boot loader at the same time support old and new layouts simultaneously. Could you please suggest an alternative approach that would enable users to update U-Boot partition? If not, then I guess, will have to drop this patch. Note that, this means there won't be a straight forward way of updating SPI U-Boot partition from kernel for K2 devices. -- Regards Vignesh
Re: [PATCH RESEND] ARM: dts: keystone-k2*: Increase SPI Flash partition size for U-Boot
On Wednesday 12 October 2016 05:27 PM, Russell King - ARM Linux wrote: > On Wed, Oct 12, 2016 at 04:30:28PM +0530, Vignesh R wrote: [...] >>> >>> - What is this "misc" partition? >>> >> >> This partition seems to exists from the very beginning. I believe, this >> is just a spare area of flash that can be used as per end-user >> requirement. Either to store a small filesystem or kernel. Copying >> Murali who added above partition if he has any input here. >> >>> - Why is it safe to move the "misc" partition in this way? >>> >>> - Do users need to do anything with data stored in the "misc" partition >>> when changing kernels? >>> >> >> MTD layer will take care of most abstractions (like start address etc). >> Will add a note in commit message informing about the reduction in size >> of the partition. >> >>> If the "misc" partition is simply unused space on the flash device, why >>> list it in DT? >>> >> >> If the unused space is not listed in the DT, then there is no /dev/mtdX >> node created for the unused section. User will then have to manually >> edit DT, in order to get the node and mount it. Instead, lets make it >> available by default. > > So, taken all together, your argument is: > > - We want a user partition > - It's okay to destroy the data in the user's partition by moving it > around randomly between kernel versions. > > The two do not naturally go together at all. You're messing with user > expectations in ways you should not be. This really is not an acceptable > approach. > Ok, I understand that if the user just updates to new kernel(w/o updating bootloader) then this patch will end up setting "misc" partition at wrong offset. At this point, I don't see how to provide a way to upgrade boot loader at the same time support old and new layouts simultaneously. Could you please suggest an alternative approach that would enable users to update U-Boot partition? If not, then I guess, will have to drop this patch. Note that, this means there won't be a straight forward way of updating SPI U-Boot partition from kernel for K2 devices. -- Regards Vignesh
Re: [PATCH RESEND] ARM: dts: keystone-k2*: Increase SPI Flash partition size for U-Boot
On Wed, Oct 12, 2016 at 04:30:28PM +0530, Vignesh R wrote: > Hi, > > On Monday 10 October 2016 08:01 PM, Russell King - ARM Linux wrote: > > On Mon, Oct 10, 2016 at 07:41:41PM +0530, Vignesh R wrote: > >> U-Boot SPI Boot image is now more than 512KB for Keystone2 devices and > >> cannot fit into existing partition. So, increase the SPI Flash partition > >> for U-Boot to 1MB for all Keystone2 devices. > >> > >> Signed-off-by: Vignesh R> >> --- > >> > >> This was submitted to v4.9 merge window but was never picked up: > >> https://patchwork.kernel.org/patch/9135023/ > > > > I think you need to explain why it's safe to change the layout of the > > flash partitions like this. > > > > - What is this "misc" partition? > > > > This partition seems to exists from the very beginning. I believe, this > is just a spare area of flash that can be used as per end-user > requirement. Either to store a small filesystem or kernel. Copying > Murali who added above partition if he has any input here. > > > - Why is it safe to move the "misc" partition in this way? > > > > - Do users need to do anything with data stored in the "misc" partition > > when changing kernels? > > > > MTD layer will take care of most abstractions (like start address etc). > Will add a note in commit message informing about the reduction in size > of the partition. > > > If the "misc" partition is simply unused space on the flash device, why > > list it in DT? > > > > If the unused space is not listed in the DT, then there is no /dev/mtdX > node created for the unused section. User will then have to manually > edit DT, in order to get the node and mount it. Instead, lets make it > available by default. So, taken all together, your argument is: - We want a user partition - It's okay to destroy the data in the user's partition by moving it around randomly between kernel versions. The two do not naturally go together at all. You're messing with user expectations in ways you should not be. This really is not an acceptable approach. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.
Re: [PATCH RESEND] ARM: dts: keystone-k2*: Increase SPI Flash partition size for U-Boot
On Wed, Oct 12, 2016 at 04:30:28PM +0530, Vignesh R wrote: > Hi, > > On Monday 10 October 2016 08:01 PM, Russell King - ARM Linux wrote: > > On Mon, Oct 10, 2016 at 07:41:41PM +0530, Vignesh R wrote: > >> U-Boot SPI Boot image is now more than 512KB for Keystone2 devices and > >> cannot fit into existing partition. So, increase the SPI Flash partition > >> for U-Boot to 1MB for all Keystone2 devices. > >> > >> Signed-off-by: Vignesh R > >> --- > >> > >> This was submitted to v4.9 merge window but was never picked up: > >> https://patchwork.kernel.org/patch/9135023/ > > > > I think you need to explain why it's safe to change the layout of the > > flash partitions like this. > > > > - What is this "misc" partition? > > > > This partition seems to exists from the very beginning. I believe, this > is just a spare area of flash that can be used as per end-user > requirement. Either to store a small filesystem or kernel. Copying > Murali who added above partition if he has any input here. > > > - Why is it safe to move the "misc" partition in this way? > > > > - Do users need to do anything with data stored in the "misc" partition > > when changing kernels? > > > > MTD layer will take care of most abstractions (like start address etc). > Will add a note in commit message informing about the reduction in size > of the partition. > > > If the "misc" partition is simply unused space on the flash device, why > > list it in DT? > > > > If the unused space is not listed in the DT, then there is no /dev/mtdX > node created for the unused section. User will then have to manually > edit DT, in order to get the node and mount it. Instead, lets make it > available by default. So, taken all together, your argument is: - We want a user partition - It's okay to destroy the data in the user's partition by moving it around randomly between kernel versions. The two do not naturally go together at all. You're messing with user expectations in ways you should not be. This really is not an acceptable approach. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.
Re: [PATCH RESEND] ARM: dts: keystone-k2*: Increase SPI Flash partition size for U-Boot
Hi, On Monday 10 October 2016 09:31 PM, Santosh Shilimkar wrote: > Vignesh, > > On 10/10/2016 7:31 AM, Russell King - ARM Linux wrote: >> On Mon, Oct 10, 2016 at 07:41:41PM +0530, Vignesh R wrote: >>> U-Boot SPI Boot image is now more than 512KB for Keystone2 devices and >>> cannot fit into existing partition. So, increase the SPI Flash partition >>> for U-Boot to 1MB for all Keystone2 devices. >>> >>> Signed-off-by: Vignesh R>>> --- >>> >>> This was submitted to v4.9 merge window but was never picked up: >>> https://patchwork.kernel.org/patch/9135023/ > > Another point is, if you want me to pick your patch, please copy > me next time :-). AFAIK, am seeing this patch in my inbox first time. > Sorry, I did address the previous patch to you. Not sure what happened :( >> >> I think you need to explain why it's safe to change the layout of the >> flash partitions like this. >> >> - What is this "misc" partition? >> >> - Why is it safe to move the "misc" partition in this way? >> >> - Do users need to do anything with data stored in the "misc" partition >> when changing kernels? >> >> If the "misc" partition is simply unused space on the flash device, why >> list it in DT? >> > Thanks Russell. Yes, above clarification would be good to get first. Ok, will send v2 with updated commit message as per my reply in other thread. -- Regards Vignesh
Re: [PATCH RESEND] ARM: dts: keystone-k2*: Increase SPI Flash partition size for U-Boot
Hi, On Monday 10 October 2016 09:31 PM, Santosh Shilimkar wrote: > Vignesh, > > On 10/10/2016 7:31 AM, Russell King - ARM Linux wrote: >> On Mon, Oct 10, 2016 at 07:41:41PM +0530, Vignesh R wrote: >>> U-Boot SPI Boot image is now more than 512KB for Keystone2 devices and >>> cannot fit into existing partition. So, increase the SPI Flash partition >>> for U-Boot to 1MB for all Keystone2 devices. >>> >>> Signed-off-by: Vignesh R >>> --- >>> >>> This was submitted to v4.9 merge window but was never picked up: >>> https://patchwork.kernel.org/patch/9135023/ > > Another point is, if you want me to pick your patch, please copy > me next time :-). AFAIK, am seeing this patch in my inbox first time. > Sorry, I did address the previous patch to you. Not sure what happened :( >> >> I think you need to explain why it's safe to change the layout of the >> flash partitions like this. >> >> - What is this "misc" partition? >> >> - Why is it safe to move the "misc" partition in this way? >> >> - Do users need to do anything with data stored in the "misc" partition >> when changing kernels? >> >> If the "misc" partition is simply unused space on the flash device, why >> list it in DT? >> > Thanks Russell. Yes, above clarification would be good to get first. Ok, will send v2 with updated commit message as per my reply in other thread. -- Regards Vignesh
Re: [PATCH RESEND] ARM: dts: keystone-k2*: Increase SPI Flash partition size for U-Boot
Hi, On Monday 10 October 2016 08:01 PM, Russell King - ARM Linux wrote: > On Mon, Oct 10, 2016 at 07:41:41PM +0530, Vignesh R wrote: >> U-Boot SPI Boot image is now more than 512KB for Keystone2 devices and >> cannot fit into existing partition. So, increase the SPI Flash partition >> for U-Boot to 1MB for all Keystone2 devices. >> >> Signed-off-by: Vignesh R>> --- >> >> This was submitted to v4.9 merge window but was never picked up: >> https://patchwork.kernel.org/patch/9135023/ > > I think you need to explain why it's safe to change the layout of the > flash partitions like this. > > - What is this "misc" partition? > This partition seems to exists from the very beginning. I believe, this is just a spare area of flash that can be used as per end-user requirement. Either to store a small filesystem or kernel. Copying Murali who added above partition if he has any input here. > - Why is it safe to move the "misc" partition in this way? > > - Do users need to do anything with data stored in the "misc" partition > when changing kernels? > MTD layer will take care of most abstractions (like start address etc). Will add a note in commit message informing about the reduction in size of the partition. > If the "misc" partition is simply unused space on the flash device, why > list it in DT? > If the unused space is not listed in the DT, then there is no /dev/mtdX node created for the unused section. User will then have to manually edit DT, in order to get the node and mount it. Instead, lets make it available by default. -- Regards Vignesh
Re: [PATCH RESEND] ARM: dts: keystone-k2*: Increase SPI Flash partition size for U-Boot
Hi, On Monday 10 October 2016 08:01 PM, Russell King - ARM Linux wrote: > On Mon, Oct 10, 2016 at 07:41:41PM +0530, Vignesh R wrote: >> U-Boot SPI Boot image is now more than 512KB for Keystone2 devices and >> cannot fit into existing partition. So, increase the SPI Flash partition >> for U-Boot to 1MB for all Keystone2 devices. >> >> Signed-off-by: Vignesh R >> --- >> >> This was submitted to v4.9 merge window but was never picked up: >> https://patchwork.kernel.org/patch/9135023/ > > I think you need to explain why it's safe to change the layout of the > flash partitions like this. > > - What is this "misc" partition? > This partition seems to exists from the very beginning. I believe, this is just a spare area of flash that can be used as per end-user requirement. Either to store a small filesystem or kernel. Copying Murali who added above partition if he has any input here. > - Why is it safe to move the "misc" partition in this way? > > - Do users need to do anything with data stored in the "misc" partition > when changing kernels? > MTD layer will take care of most abstractions (like start address etc). Will add a note in commit message informing about the reduction in size of the partition. > If the "misc" partition is simply unused space on the flash device, why > list it in DT? > If the unused space is not listed in the DT, then there is no /dev/mtdX node created for the unused section. User will then have to manually edit DT, in order to get the node and mount it. Instead, lets make it available by default. -- Regards Vignesh
Re: [PATCH RESEND] ARM: dts: keystone-k2*: Increase SPI Flash partition size for U-Boot
Vignesh, On 10/10/2016 7:31 AM, Russell King - ARM Linux wrote: On Mon, Oct 10, 2016 at 07:41:41PM +0530, Vignesh R wrote: U-Boot SPI Boot image is now more than 512KB for Keystone2 devices and cannot fit into existing partition. So, increase the SPI Flash partition for U-Boot to 1MB for all Keystone2 devices. Signed-off-by: Vignesh R--- This was submitted to v4.9 merge window but was never picked up: https://patchwork.kernel.org/patch/9135023/ Another point is, if you want me to pick your patch, please copy me next time :-). AFAIK, am seeing this patch in my inbox first time. I think you need to explain why it's safe to change the layout of the flash partitions like this. - What is this "misc" partition? - Why is it safe to move the "misc" partition in this way? - Do users need to do anything with data stored in the "misc" partition when changing kernels? If the "misc" partition is simply unused space on the flash device, why list it in DT? Thanks Russell. Yes, above clarification would be good to get first.
Re: [PATCH RESEND] ARM: dts: keystone-k2*: Increase SPI Flash partition size for U-Boot
Vignesh, On 10/10/2016 7:31 AM, Russell King - ARM Linux wrote: On Mon, Oct 10, 2016 at 07:41:41PM +0530, Vignesh R wrote: U-Boot SPI Boot image is now more than 512KB for Keystone2 devices and cannot fit into existing partition. So, increase the SPI Flash partition for U-Boot to 1MB for all Keystone2 devices. Signed-off-by: Vignesh R --- This was submitted to v4.9 merge window but was never picked up: https://patchwork.kernel.org/patch/9135023/ Another point is, if you want me to pick your patch, please copy me next time :-). AFAIK, am seeing this patch in my inbox first time. I think you need to explain why it's safe to change the layout of the flash partitions like this. - What is this "misc" partition? - Why is it safe to move the "misc" partition in this way? - Do users need to do anything with data stored in the "misc" partition when changing kernels? If the "misc" partition is simply unused space on the flash device, why list it in DT? Thanks Russell. Yes, above clarification would be good to get first.
Re: [PATCH RESEND] ARM: dts: keystone-k2*: Increase SPI Flash partition size for U-Boot
On Mon, Oct 10, 2016 at 07:41:41PM +0530, Vignesh R wrote: > U-Boot SPI Boot image is now more than 512KB for Keystone2 devices and > cannot fit into existing partition. So, increase the SPI Flash partition > for U-Boot to 1MB for all Keystone2 devices. > > Signed-off-by: Vignesh R> --- > > This was submitted to v4.9 merge window but was never picked up: > https://patchwork.kernel.org/patch/9135023/ I think you need to explain why it's safe to change the layout of the flash partitions like this. - What is this "misc" partition? - Why is it safe to move the "misc" partition in this way? - Do users need to do anything with data stored in the "misc" partition when changing kernels? If the "misc" partition is simply unused space on the flash device, why list it in DT? -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.
Re: [PATCH RESEND] ARM: dts: keystone-k2*: Increase SPI Flash partition size for U-Boot
On Mon, Oct 10, 2016 at 07:41:41PM +0530, Vignesh R wrote: > U-Boot SPI Boot image is now more than 512KB for Keystone2 devices and > cannot fit into existing partition. So, increase the SPI Flash partition > for U-Boot to 1MB for all Keystone2 devices. > > Signed-off-by: Vignesh R > --- > > This was submitted to v4.9 merge window but was never picked up: > https://patchwork.kernel.org/patch/9135023/ I think you need to explain why it's safe to change the layout of the flash partitions like this. - What is this "misc" partition? - Why is it safe to move the "misc" partition in this way? - Do users need to do anything with data stored in the "misc" partition when changing kernels? If the "misc" partition is simply unused space on the flash device, why list it in DT? -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.