Commit Graph

14 Commits

Author SHA1 Message Date
Vignesh R a27f2eaf2b mtd: spi-nor: cadence-quadspi: Add support for direct access mode
Cadence QSPI controller provides direct access mode through which flash
can be accessed in a memory-mapped IO mode. This enables read/write to
flash using memcpy*() functions. This mode provides higher throughput
for both read/write operations when compared to current indirect mode of
operation.

This patch therefore adds support to use QSPI in direct mode. If the
window reserved in SoC's memory map for MMIO access is less that of
flash size(like on most SoCFPGA variants), then the driver falls back
to indirect mode of operation.

On TI's 66AK2G SoC, with ARM running at 600MHz and QSPI at 96MHz
switching to direct mode improves read throughput from 3MB/s to 8MB/s.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
2018-01-07 18:54:58 +01:00
Vignesh R e4b580bc04 mtd: spi-nor: cadence-quadspi: Refactor indirect read/write sequence.
Move configuring of indirect read/write start address to
cqspi_indirect_*_execute() function and rename cqspi_indirect_*_setup()
function. This will help to reuse cqspi_indirect_*_setup() function for
supporting direct access mode.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
2018-01-07 18:53:13 +01:00
Vignesh R 4892b374c9 mtd: spi-nor: cadence-quadspi: Add runtime PM support
Add pm_runtime* calls to cadence-quadspi driver. This is required to
switch on QSPI power domain on TI 66AK2G SoC during probe.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
2017-10-17 20:42:10 +02:00
Vignesh R 329864d35a mtd: spi-nor: cadence-quadspi: Fix error path in probe
Fix the reversed goto labels, so that we disable cqspi controller only
if its enabled previously. This is a minor cleanup.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
2017-10-17 20:41:19 +02:00
Vignesh R e2580a4add mtd: spi-nor: cadence-quadspi: Add support to enable loop-back clock circuit
Cadence QSPI IP has a adapted loop-back circuit which can be enabled by
setting BYPASS field to 0 in READCAPTURE register. It enables use of
QSPI return clock to latch the data rather than the internal QSPI
reference clock. For high speed operations, adapted loop-back circuit
using QSPI return clock helps to increase data valid window.

Based on DT parameter cdns,rclk-en enable adapted loop-back circuit
for boards which do have QSPI return clock provided.
This patch also modifies cqspi_readdata_capture() function's bypass
parameter to bool to match how its used in the function.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
2017-10-17 20:40:22 +02:00
Vignesh R 61dc8493ba mtd: spi-nor: cadence-quadspi: add a delay in write sequence
As per 66AK2G02 TRM[1] SPRUHY8F section 11.15.5.3 Indirect Access
Controller programming sequence, a delay equal to couple of QSPI master
clock(~5ns) is required after setting CQSPI_REG_INDIRECTWR_START bit and
writing data to the flash. Introduce a quirk flag CQSPI_NEEDS_WR_DELAY
to handle this and set this flag for TI 66AK2G SoC.

[1]http://www.ti.com/lit/ug/spruhy8f/spruhy8f.pdf

Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
2017-10-17 20:38:27 +02:00
Arnd Bergmann 315e9c767d mtd: spi-nor: cqspi: remove duplicate const
The variable was already marked 'const' before the previous
patch, but the qualifier was in an unusual place, and now the
extra 'const' causes a harmless warning:

drivers/mtd/spi-nor/cadence-quadspi.c:1286:34: error: duplicate 'const' declaration specifier [-Werror=duplicate-decl-specifier]

This removes the other 'const' instead.

Fixes: f993c123b4 ("mtd: spi-nor: cqspi: make of_device_ids const")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
2017-06-27 21:28:52 +02:00
Arvind Yadav f993c123b4 mtd: spi-nor: cqspi: make of_device_ids const
of_device_ids are not supposed to change at runtime. All functions
working with of_device_ids provided by <linux/of.h> work with const
of_device_ids. So mark the non-const structs as const.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
2017-06-20 23:54:18 +02:00
Cyrille Pitchen cfc5604c48 mtd: spi-nor: introduce SPI 1-2-2 and SPI 1-4-4 protocols
This patch changes the prototype of spi_nor_scan(): its 3rd parameter
is replaced by a 'struct spi_nor_hwcaps' pointer, which tells the spi-nor
framework about the actual hardware capabilities supported by the SPI
controller and its driver.

Besides, this patch also introduces a new 'struct spi_nor_flash_parameter'
telling the spi-nor framework about the hardware capabilities supported by
the SPI flash memory and the associated settings required to use those
hardware caps.

Then, to improve the readability of spi_nor_scan(), the discovery of the
memory settings and the memory initialization are now split into two
dedicated functions.

1 - spi_nor_init_params()

The spi_nor_init_params() function is responsible for initializing the
'struct spi_nor_flash_parameter'. Currently this structure is filled with
legacy values but further patches will allow to override some parameter
values dynamically, for instance by reading the JESD216 Serial Flash
Discoverable Parameter (SFDP) tables from the SPI memory.
The spi_nor_init_params() function only deals with the hardware
capabilities of the SPI flash memory: especially it doesn't care about
the hardware capabilities supported by the SPI controller.

2 - spi_nor_setup()

The second function is called once the 'struct spi_nor_flash_parameter'
has been initialized by spi_nor_init_params().
With both 'struct spi_nor_flash_parameter' and 'struct spi_nor_hwcaps',
the new argument of spi_nor_scan(), spi_nor_setup() computes the best
match between hardware caps supported by both the (Q)SPI memory and
controller hence selecting the relevant settings for (Fast) Read and Page
Program operations.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
2017-05-15 21:56:17 +02:00
Colin Ian King 7fa2c7038c mtd: spi-nor: cqspi: remove redundant dead code on error return check
Checking for ret < 0 is redundant because a previous check on ret
being non-zero already handles the ret < 0 case. Remove the redundant
code. Found by CoverityScan, CID#1398863, CID#1398864

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
2017-02-10 14:22:00 +01:00
Marek Vasut 0cf1725676 mtd: spi-nor: cqspi: Fix build on arches missing readsl/writesl
The x86-64 and some other architectures are missing readsl/writesl
functions, so this driver won't build on them. Use a more portable
ioread32_rep()/iowrite32_rep() instead.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alan Tull <atull@opensource.altera.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dinh Nguyen <dinguyen@opensource.altera.com>
Cc: Graham Moore <grmoore@opensource.altera.com>
Cc: Vignesh R <vigneshr@ti.com>
Cc: Yves Vandervennet <yvanderv@opensource.altera.com>
Suggested-by: Stefan Roese <sr@denx.de>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
2017-01-04 09:54:03 +01:00
Dan Carpenter 10ad1d754a mtd: spi-nor: Fix some error codes in cqspi_setup_flash()
We return success or possibly uninitialized values on these error paths
instead of proper error codes.

Fixes: 1406234105 ("mtd: spi-nor: Add driver for Cadence Quad SPI Flash Controller")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Moritz Fischer <moritz.fischer@ettus.com>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
2016-11-26 16:50:13 +01:00
Dan Carpenter 193e87143c mtd: spi-nor: Off by one in cqspi_setup_flash()
There are CQSPI_MAX_CHIPSELECT elements in the ->f_pdata array so the >
should be >=.

Fixes: 1406234105 ('mtd: spi-nor: Add driver for Cadence Quad SPI Flash Controller')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
2016-11-26 16:50:03 +01:00
Graham Moore 1406234105 mtd: spi-nor: Add driver for Cadence Quad SPI Flash Controller
Add support for the Cadence QSPI controller. This controller is
present in the Altera SoCFPGA SoCs and this driver has been tested
on the Cyclone V SoC.

Signed-off-by: Graham Moore <grmoore@opensource.altera.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alan Tull <atull@opensource.altera.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dinh Nguyen <dinguyen@opensource.altera.com>
Cc: Graham Moore <grmoore@opensource.altera.com>
Cc: Vignesh R <vigneshr@ti.com>
Cc: Yves Vandervennet <yvanderv@opensource.altera.com>
Cc: devicetree@vger.kernel.org
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-07-18 10:00:23 -07:00