On Tue, Dec 12, 2017 at 11:44 AM, Prabhakar Kushwaha prabhakar.kushwaha@nxp.com wrote:
Hi Marek,
-----Original Message----- From: Marek Vasut [mailto:marek.vasut@gmail.com] Sent: Monday, December 11, 2017 3:04 PM To: Prabhakar Kushwaha prabhakar.kushwaha@nxp.com; u- boot@lists.denx.de Cc: jagannadh.teki@gmail.com; Poonam Aggrwal poonam.aggrwal@nxp.com; Suresh Gupta suresh.gupta@nxp.com; cyrille.pitchen@atmel.com Subject: Re: [RFC 0/5] sf: Update spi-nor framework
On 12/11/2017 06:57 AM, Prabhakar Kushwaha wrote:
SPI-NOR framework currently supports-
- (1-1-1, 1-1-2, 1-1-4) read protocols
- read latency(dummy bytes) are hardcoded with the assumption
that the flash would support it.
- No support of mode bits.
- No support of flash size above 128Mib
This patch set add support of 1-2-2, 1-4-4 read protocols. It ports Linux commits "mtd: spi-nor: add a stateless method to support memory size above 128Mib" and "mtd: spi-nor: parse Serial Flash Discoverable Parameters (SFDP) tables". It enables 4byte address opcode and run time flash parameters discovery including dummy cycle and mode cycle.
Finally it update fsl-quadspi driver to store(set_mode) spi bus mode and provision for run-time LUTs creation.
Note: This patch-set is only **compliation** tested. Sending RFC to get early feed-back on the approach.
Prabhakar Kushwaha (5): sf: Add support of 1-2-2, 1-4-4 IO READ protocols sf: add method to support memory size above 128Mib sf: parse Serial Flash Discoverable Parameters (SFDP) tables sf: fsl_qspi: Add support of fsl_qspi_set_mode sf: fsl_quadspi: Configue LUT based on padding information
drivers/mtd/spi/sf_internal.h | 230 +++++++++++++++- drivers/mtd/spi/spi_flash.c | 574
+++++++++++++++++++++++++++++++++++++++-
drivers/spi/fsl_qspi.c | 85 +++++- include/spi_flash.h | 2 + 5 files changed, 875 insertions(+), 18 deletions(-)
Could you rather port the entire SPI NOR framework from Linux 4.14 ? That'd make more sense than porting bits and pieces on top of the current crappy code IMO.
I agree with you. Linux 4.14 SPI NOR framework should be ported. I may not able to do this because of bandwidth and lack of expertise. I will request Jagan (custodian) to look into this.
This RFC patch-set can easily be applied to existing and ported Linux SPI NOR framework when it gets available.
For now, I think these patches(the next version) with the existing framework can be reviewed and accepted. Please help to share your views.
For next version of this patch set, I will be working on testing it to enable other flashes. It will also help Jagan during 4.14 porting. Jagan, your views?
direct-porting from Linux is not so optimal(not well suited for U-Boot design) as I've tried before. We're working on the dm-driven spi-nor. So I will continue to review your patches on current code and will see how we can merge the same once dm-spi-nor available.
Jagan.