mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

mtd: spi-nor: cadence-quadspi: add reset control 

Get the reset control properties for the QSPI controller and bring them
out of reset. Most will have just one reset bit, but there is an additional
OCP reset bit that is used ECC. The OCP reset bit will also need to get
de-asserted as well. [1]

The reason this patch is needed is in the case where a bootloader leaves
the QSPI controller in a reset state, or a state where init cannot occur
successfully, the patch will put the QSPI controller into a clean state.

[1] https://www.intel.com/content/www/us/en/programmable/hps/arria-10/hps.html#reg_soc_top/sfo1429890575955.html

Suggested-by: Tien-Fong Chee <tien.fong.chee@intel.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
[tudor.ambarus@microchip.com: declare rstc and rstc_ocp on the same line]
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
This commit is contained in:
Dinh Nguyen 2019-06-13 06:31:38 -05:00 committed by Tudor Ambarus
parent 63d3cd297b
commit 8d1336c241
No known key found for this signature in database
GPG Key ID: 4B554F47A58D14E9
1 changed files with 21 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
drivers/mtd/spi-nor/cadence-quadspi.c
View File

@ -34,6 +34,7 @@
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/reset.h>
#include <linux/sched.h>
#include <linux/spi/spi.h>
#include <linux/timer.h>
@ -1336,6 +1337,7 @@ static int cqspi_probe(struct platform_device *pdev)
struct cqspi_st *cqspi;
struct resource *res;
struct resource *res_ahb;
struct reset_control *rstc, *rstc_ocp;
const struct cqspi_driver_platdata *ddata;
int ret;
int irq;
@ -1402,6 +1404,25 @@ static int cqspi_probe(struct platform_device *pdev)
goto probe_clk_failed;
}
/* Obtain QSPI reset control */
rstc = devm_reset_control_get_optional_exclusive(dev, "qspi");
if (IS_ERR(rstc)) {
dev_err(dev, "Cannot get QSPI reset.\n");
return PTR_ERR(rstc);
}
rstc_ocp = devm_reset_control_get_optional_exclusive(dev, "qspi-ocp");
if (IS_ERR(rstc_ocp)) {
dev_err(dev, "Cannot get QSPI OCP reset.\n");
return PTR_ERR(rstc_ocp);
}
reset_control_assert(rstc);
reset_control_deassert(rstc);
reset_control_assert(rstc_ocp);
reset_control_deassert(rstc_ocp);
cqspi->master_ref_clk_hz = clk_get_rate(cqspi->clk);
ddata = of_device_get_match_data(dev);
if (ddata && (ddata->quirks & CQSPI_NEEDS_WR_DELAY))