dmaengine: altera-msgdma: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new() which already returns void. Eventually after all drivers
are converted, .remove_new() is renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Olivier Dautricourt <olivierdautricourt@gmail.com>
Link: https://lore.kernel.org/r/20230919133207.1400430-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: altera-msgdma: Fixed some inconsistent function name descriptions

Inconsistent function names describing msgdma_chan_remove() and
msgdma_dma_remove are modified to msgdma_dev_remove() and msgdma_remove().

Remove some warnings found by running scripts/kernel-doc, which is caused
by using 'make W=1'.

drivers/dma/altera-msgdma.c:927: warning: expecting prototype for msgdma_dma_remove(). Prototype was for msgdma_remove() instead.
drivers/dma/altera-msgdma.c:758: warning: expecting prototype for msgdma_chan_remove(). Prototype was for msgdma_dev_remove() instead.

Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Link: https://lore.kernel.org/r/20220706082605.114907-1-jiapeng.chong@linux.alibaba.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: altera-msgdma: Remove useless DMA-32 fallback configuration

As stated in [1], dma_set_mask() with a 64-bit mask never fails if
dev->dma_mask is non-NULL.
So, if it fails, the 32 bits case will also fail for the same reason.

Simplify code and remove some dead code accordingly.

[1]: https://lore.kernel.org/linux-kernel/YL3vSPK5DXTNvgdx@infradead.org/#t

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Stefan Roese <sr@denx.de>
Acked-by: Olivier Dautricourt <olivier.dautricourt@orolia.com>
Link: https://lore.kernel.org/r/01058ada3a0dea207212182ca7525060a204f1e1.1642232423.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: altera-msgdma: Correctly handle descriptor callbacks

DMA clients can provide one of two types of callbacks. For this reason
dmaengine drivers should not directly invoke `callback`, but always use
dmaengine_desc_callback_invoke(). This makes sure that both types of
callbacks are handled correctly.

The altera-msgdma driver currently doesn't do this and only handles the
`callback` type callback. If the client used the `callback_result` type
callback it will not be called.

Fix this by switching to `dmaengine_desc_callback_valid()` and
`dmaengine_desc_callback_invoke()`.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20211025075428.2094-1-lars@metafoo.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: altera-msgdma: make response port optional

The response slave port can be disabled in some configuration [1] and
csr + MSGDMA_CSR_RESP_FILL_LEVEL will be 0 even if transfer has suceeded.
We have to only rely on the interrupts in that scenario.
This was tested on cyclone V with the controller resp port disabled.

[1] https://www.intel.com/content/www/us/en/programmable/documentation/sfo1400787952932.html
30.3.1.2
30.3.1.3
30.5.5

Fixes: https://forum.rocketboards.org/t/ip-msgdma-linux-driver/1919
Signed-off-by: Olivier Dautricourt <olivier.dautricourt@orolia.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Link: https://lore.kernel.org/r/8220756f2191ca08cb21702252d1f2d4f753a7f5.1623898678.git.olivier.dautricourt@orolia.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: altera-msgdma: add OF support

This driver had no device tree support.

- add compatible field "altr,socfpga-msgdma"
- register dma controller with of_dma_controller_register

Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Olivier Dautricourt <olivier.dautricourt@orolia.com>
Link: https://lore.kernel.org/r/7459635ba093d87b6bf12413cf7cfe09f6e3019b.1623251990.git.olivier.dautricourt@orolia.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: altera-msgdma: fix kernel-doc style for tasklet

Commit 6752e40d669a ("dmaengine: altera-msgdma: convert tasklets to use
new tasklet_setup() API") updated driver to use new tasklet_setup() API
but missed to update the documentation for the tasklet function.

Fixes: 6752e40d669a ("dmaengine: altera-msgdma: convert tasklets to use new tasklet_setup() API")
Link: https://lore.kernel.org/r/20201007083113.567559-2-vkoul@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: altera-msgdma: convert tasklets to use new tasklet_setup() API

In preparation for unconditionally passing the
struct tasklet_struct pointer to all tasklet
callbacks, switch to using the new tasklet_setup()
and from_tasklet() to pass the tasklet pointer explicitly.

Signed-off-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Allen Pais <allen.lkml@gmail.com>
Link: https://lore.kernel.org/r/20200831103542.305571-2-allen.lkml@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: altera-msgdma: Fix struct documentation blocks

Fix some misspelling/description issues, demote non-kerneldoc header
to standard comment block and provide a new description for
msgdma_desc_config()'s 'stride' parameter.

Fixes the following W=1 kernel build warning(s):

drivers/dma/altera-msgdma.c:163: warning: Function parameter or member 'node' not described in 'msgdma_sw_desc'
drivers/dma/altera-msgdma.c:163: warning: Function parameter or member 'tx_list' not described in 'msgdma_sw_desc'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'lock' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'dev' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'irq_tasklet' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'pending_list' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'free_list' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'active_list' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'done_list' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'desc_free_cnt' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'idle' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'dmadev' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'dmachan' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'hw_desq' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'sw_desq' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'npendings' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'slave_cfg' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'irq' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'csr' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'desc' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:197: warning: Function parameter or member 'resp' not described in 'msgdma_device'
drivers/dma/altera-msgdma.c:265: warning: Function parameter or member 'stride' not described in 'msgdma_desc_config'

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Cc: Stefan Roese <sr@denx.de>
Link: https://lore.kernel.org/r/20200714111546.1755231-8-lee.jones@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

remove ioremap_nocache and devm_ioremap_nocache

ioremap has provided non-cached semantics by default since the Linux 2.6
days, so remove the additional ioremap_nocache interface.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dmaengine: altera: Use IRQ-safe spinlock calls in the error paths as well

The patch edf10919 [dmaengine: altera: fix spinlock usage] missed to
change 2 occurrences of spin_unlock_bh() to spin_unlock_irqrestore().
This patch fixes this by moving to the IRQ-safe call in the error
paths as well.

Fixes: edf10919 (dmaengine: altera: fix spinlock usage)
Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Sylvain Lesne <lesne@alse-fr.com>
[add fixes tag and fix typo in log]
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: altera: fix spinlock usage

Since this lock is acquired in both process and IRQ context, failing to
to disable IRQs when trying to acquire the lock in process context can
lead to deadlocks.

Signed-off-by: Sylvain Lesne <lesne@alse-fr.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: altera: fix response FIFO emptying

Commit 6084fc2ec478 ("dmaengine: altera: Use macros instead of structs
to describe the registers") introduced a minus sign before a register
offset.

This leads to soft-locks of the DMA controller, since reading the last
status byte is required to pop the response from the FIFO. Failing to
do so will lead to a full FIFO, which means that the DMA controller
will stop processing descriptors.

Signed-off-by: Sylvain Lesne <lesne@alse-fr.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: altera: Use macros instead of structs to describe the registers

This patch moves from a struct declaration for the DMA controller
registers to macros with offests to the base address. This is mainly
done to remove the sparse warnings, since the function parameter of
ioread32/iowrite32 is "void __iomem *" instead of a pointer to struct
members. With this patch applied, no sparse warning is seen anymore.

Please note that the struct for the descriptors is still kept in place,
as the code largely accesses the struct members as internal variables
before the complete struct is copied into the descriptor FIFO of the
DMA controller.

Additionally this patch also removes two warnings "variable xxx set but
not used" seen when compiling with "W=1". The registers need to be read
to flush the response FIFO, but nothing needs to be done with them. So
the code is correct here and the warning is a false one.

Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: altera: remove DMA_SG

Commit c678fa66341c: ("dmaengine: remove DMA_SG as it is dead code in
kernel") removes DMA_SG from dmaengine subsystem but missed the newly added
driver, so remove it from here as well

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: Add driver for Altera / Intel mSGDMA IP core

This driver adds support for the Altera / Intel modular Scatter-Gather
Direct Memory Access (mSGDMA) intellectual property (IP) to the Linux
DMAengine subsystem. Currently it supports the following op modes:

- DMA_MEMCPY
- DMA_SG
- DMA_SLAVE

This implementation has been tested on an Altera Cyclone FPGA connected
via PCIe, both on an ARM and an x86 platform.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>