Due to the controller limitation to keep the chip select low during the
bus idle time between the transfer, a dummy cs workaround was used when
this driver was first upstreamed to the u-boot based on linux kernel
driver. It basically picks the dummy cs as !actual_cs so typically dummy
cs is 1 when most of the case only cs 0 is used in the board design.
Then invert the polarity of both cs and tell the controller to start the
transfers using dummy cs. Assuming both cs are active low before the
inversion, effectively this keeps dummy cs high and actual cs low during
the transfer and workaround the issue.
This workaround requires that dummy cs 1 pin to is set to SPI chip
selection function in the pinmux when the transfer clock is above 25MHz.
The old chips likely have default pinmux set to chip select on the dummy
cs pin so it works but this is not case for the new Broadband BCA chips
and this workaround stop working. This is specifically an issue to
support SPI NAND and SPI NOR flash because these flash devices can
typically run at or above 100MHz.
This patch utilizes the prepend feature of the controller to combine the
multiple transfers in the same message to a single transfer when
possible. This way there is no need to keep clock low between transfers
and solve the issue without any pinmux requirement.
Multiple transfers within a SPI message may be combined into one
transfer if the following are all true:
* One or more half duplex write transfer in single bit mode
* Optional full duplex read/write at the end
* No delay and cs_change between transfers
Most of the SPI device meets this requirements such as SPI NOR, SPI NAND
flash, Broadcom SPI voice card and etc. So this change switches to the
prepend mode as the default mode. For any SPI message that does not meet
the above requirement, we switch to original dummy cs mode but limit the
clock rate to the safe 25MHz.
Port from linux patch:
Link: https://lore.kernel.org/r/20230209200246.141520-12-william.zhang@broadcom.com
Signed-off-by: William Zhang <william.zhang@broadcom.com>
Acked-by: Jagan Teki <jagan@amarulasolutions.com>
New compatible string brcm,bcmbca-hsspi-v1.0 is introduced based on
dts document brcm,bcm63xx-hsspi.yaml. Add it to the driver to support
this new binding.
Port from linux patch:
Link: https://lore.kernel.org/r/20230207065826.285013-6-william.zhang@broadcom.com
Signed-off-by: William Zhang <william.zhang@broadcom.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Currently the driver always sets the controller to dual data bit mode
for both tx and rx data in the profile mode control register even for
single data bit transfer. Luckily the opcode is set correctly according
to SPI transfer data bit width so it does not actually cause issues.
This change fixes the problem by setting tx and rx data bit mode field
correctly according to the actual SPI transfer tx and rx data bit width.
Fixes: 29cc4368ad ("dm: spi: add BCM63xx HSSPI driver")
Port from linux patch:
Link: https://lore.kernel.org/r/20230209200246.141520-11-william.zhang@broadcom.com
Signed-off-by: William Zhang <william.zhang@broadcom.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Fix some typos in spi drivers
Signed-off-by: Pengfei Fan <fanpengfei1@eswincomputing.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
We use 'priv' for private data but often use 'platdata' for platform data.
We can't really use 'pdata' since that is ambiguous (it could mean private
or platform data).
Rename some of the latter variables to end with 'plat' for consistency.
Signed-off-by: Simon Glass <sjg@chromium.org>
This construct is quite long-winded. In earlier days it made some sense
since auto-allocation was a strange concept. But with driver model now
used pretty universally, we can shorten this to 'auto'. This reduces
verbosity and makes it easier to read.
Coincidentally it also ensures that every declaration is on one line,
thus making dtoc's job easier.
Signed-off-by: Simon Glass <sjg@chromium.org>
At present dm/device.h includes the linux-compatible features. This
requires including linux/compat.h which in turn includes a lot of headers.
One of these is malloc.h which we thus end up including in every file in
U-Boot. Apart from the inefficiency of this, it is problematic for sandbox
which needs to use the system malloc() in some files.
Move the compatibility features into a separate header file.
Signed-off-by: Simon Glass <sjg@chromium.org>
We need distinguish the following two situations in various SPI APIs:
- given chip select num is invalid
- given chip select num is valid, but no device is attached
Currently -ENODEV is returned for both cases.
For the first case, it's more reasonable to return -EINVAL instead of
-ENODEV for invalid chip select numbers.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> # SoPine
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
The Broadcom ARM implementations do not yet have a clock framework so
one can use a fixed clock as the root clock of the hsspi block. The
fixed clock does not have an "enable" routine, since it's always
enabled. So when we hit this issue, getting an ENOSYS return, do not
bail but continue initialization.
Similarly the block might already have been out of reset, say, when
we are booting from a SPI device. So if the reset signal is not configured
in the device tree, do not bail out and instead skip deasserting the reset.
Signed-off-by: Kursad Oney <kursad.oney@broadcom.com>
Reviewed-by: Philippe Reynes <philippe.reynes@softathome.com>
Make the driver compatible with both big and little endian SOCs.
Replace big-endian calls with their raw equivalents, expect for
writing the command to FIFO. That still has to be in big-endian
format.
Signed-off-by: Kursad Oney <kursad.oney@broadcom.com>
Reviewed-by: Philippe Reynes <philippe.reynes@softathome.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from. So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry. Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.
In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.
This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents. There's also a few places where I found we did not have a tag
and have introduced one.
Signed-off-by: Tom Rini <trini@konsulko.com>
This driver is a simplified version of linux/drivers/spi/spi-bcm63xx-hsspi.c
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>
