[U-Boot] [PATCH] sf: Fix s25fs512s erase size and remove SECT_4K flag

[Suresh Gupta]

> -----Original Message-----
> From: Suresh Gupta
> Sent: Monday, June 12, 2017 2:18 PM
> To: 'Jagan Teki' <jagannadh.teki at gmail.com>
> Cc: Jagan Teki <jagan at amarulasolutions.com>; york sun <york.sun at nxp.com>;
> u-boot at lists.denx.de; Jagan Teki <jagan at openedev.com>; Yao Yuan
> <yao.yuan at nxp.com>
> Subject: RE: [U-Boot] [PATCH] sf: Fix s25fs512s erase size and remove SECT_4K
> flag
> 
> 
> 
> > -----Original Message-----
> > From: Jagan Teki [mailto:jagannadh.teki at gmail.com]
> > Sent: Monday, June 12, 2017 11:37 AM
> > To: Suresh Gupta <suresh.gupta at nxp.com>
> > Cc: Jagan Teki <jagan at amarulasolutions.com>; york sun
> > <york.sun at nxp.com>; u-boot at lists.denx.de; Jagan Teki
> > <jagan at openedev.com>; Yao Yuan <yao.yuan at nxp.com>
> > Subject: Re: [U-Boot] [PATCH] sf: Fix s25fs512s erase size and remove
> > SECT_4K flag
> >
> > Hi Suresh,
> >
> > On Thu, Jun 8, 2017 at 1:00 PM, Suresh Gupta <suresh.gupta at nxp.com>
> wrote:
> > > <snip>
> > >> >
> > >> > So best way is to disable hybrid mode and configure flash in
> > >> > Uniform Sector Architecture
> > >>
> > >> OK, then send patches to Linux and U-Boot will review and take
> > >> other suggestions too.
> > >>
> > >
> > > Thanks Jagan,
> > > I will send U-boot patches (after testing) by early next week.
> > >
> > > My next point :) to discuss is "32-bit address options".
> > > This particular flash do not support below commands
> > > /* Bank addr access commands */
> > > #ifdef CONFIG_SPI_FLASH_BAR
> > > # define CMD_BANKADDR_BRWR              0x17
> > > # define CMD_BANKADDR_BRRD              0x16
> > > # define CMD_EXTNADDR_WREAR             0xC5
> > > # define CMD_EXTNADDR_RDEAR             0xC8
> > > #endif
> > >
> > > Instead  of above S25FS512S flash support 32-bit address commands
> > > like 4READ, 4P4E and many more which require 32 bit address directly
> > > pass on
> > wires.
> > >
> > > Jagan,
> > > So, Do we have any plan to fix this?
> > > Yao Yuan already send one patch [1] for same.
> > > I think this is a decent approach [1]. If required I will resend
> > > this patch with
> > little changes.
> >
> > Don't know whether you tried this or not.
> >
> > - Erase bottom 4K sectors using 4K
> > - Erase middle sectors using SE
> > - Erase top 4K sectors using 4K
> 
> I will try all combinations and let you know the results.
> 
Jagan,
The problem here is, I have all board in which we disable hybrid mode and we write this in nonvolatile register.
So on my boards 4K erase (0x20) is not working on any of the sectors. 
Please suggest. 

Hybrid mode of this flash supports,
	- Physical set of eight 4-kbytes sectors and 
              - one 224-kbytes sector at the top or bottom of address space with 
              - all remaining sectors of 256 kbytes. 
So even if we are able to erase eight sectors via cmd 4K and rest via 256 kbyte(0xd8)
Then what about one sector of 224 Kbytes. 
And how we tell user about this erase pattern. 

Again, my suggestion is to disable hybrid mode (volatile) and we may revisit if anyone come up with different approach   
Please suggest. 

Thanks 
SuresH
 

> >
> > thanks!
> > --
> > Jagan Teki
> > Free Software Engineer | www.openedev.com U-Boot, Linux | Upstream
> > Maintainer Hyderabad, India.