MIPI I3C HCI on Intel hardware requires a quirk where ring needs to stop
and set to run again after resuming the halted controller. This is not
expected from the MIPI I3C HCI specification and is Intel specific.
Add this quirk to generic aborted transfer handling and execute it only
when ring is not in running state after a transfer error and attempted
controller resume. This is the case on Intel hardware.
It is not fully clear to me what is the ring running state in generic
hardware in such case. I would expect if ring is not running, then stop
request is a no-op and run request is either required or does the same
what controller resume would do.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20241231115904.620052-1-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Current MIPI I3C HCI specification versions pre-1.0, 1.0. 1.1 and 1.2
don't have cascaded interrupt bits for the PIO and DMA (ring headers) in
the INTR_STATUS register as implemented currently in the code. Instead
bits 9:0 are marked as reserved with unspecified reset value.
To my understanding they were planned to be introduced in the version 2
and the original commit 9ad9a52cce ("i3c/master: introduce the
mipi-i3c-hci driver") was coding ahead according to a draft. With
remarks though.
This is causing that the DMA handler is not called until at least one
reserved bit 7:0 is set in the INTR_STATUS.
Since it looks that idea was dropped in later official versions and to
make able to handle DMA interrupts on an HW that is implemented
according to current specifications call assigned PIO or DMA IO handler
unconditionally.
While doing so remove cascaded interrupt bit definitions and the mask
argument passed to the handler functions.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20240920144432.62370-3-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Bus cleanup path in DMA mode may trigger a RING_OP_STAT interrupt when
the ring is being stopped. Depending on timing between ring stop request
completion, interrupt handler removal and code execution this may lead
to a NULL pointer dereference in hci_dma_irq_handler() if it gets to run
after the io_data pointer is set to NULL in hci_dma_cleanup().
Prevent this my masking the ring interrupts before ring stop request.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20240920144432.62370-2-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The dma.c: hci_dma_init() sets the CHUNK_SIZE field in the IBI_SETUP
register incorrectly if the calculated ibi_chunk_sz is not exactly
2^(n+2) bytes, where n is 0..6.
Fix this by rounding the chunk size up to nearest 2^(n+2) bytes.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20240628131559.502822-4-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Definitely condition dma_get_cache_alignment * defined value > 256
during driver initialization is not reason to BUG_ON(). Turn that to
graceful error out with -EINVAL.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20240628131559.502822-3-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
IBI Status and Data Ring base address registers are not set so HW
obviously cannot update those rings after In-Band Interrupt.
Set them to already allocated and mapped ring addresses.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20240628131559.502822-2-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Rather than having own lo32()/hi32() helpers for dealing with 32-bit and
64-bit build targets switch to generic lower_32_bits()/upper_32_bits()
helpers.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20240628131559.502822-1-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Implement a local bounce buffer for private I3C SDR and I2C transfers
when using DMA and the buffer attached to the transfer is not DMA safe.
Otherwise the DMA transfer will fail and with following warning:
[ 11.411059] i3c mipi-i3c-hci.0: rejecting DMA map of vmalloc memory
[ 11.417313] WARNING: CPU: 3 PID: 357 at include/linux/dma-mapping.h:332 hci_dma_queue_xfer+0x2e2/0x300 [mipi_i3c_hci]
Strictly speaking private I3C SDR transfers are expected to pass a
DMA-able buffer. However I fear this requirement may easily be slipped
or go unnoticed when I3C interface support is added into a existing
device driver that use regmap API to read/write stack variables.
For example this is the case with the commit 2660b0080b ("iio: imu:
st_lsm6dsx: add i3c basic support for LSM6DSO and LSM6DSR").
Buffer of an I2C message is not required to be DMA safe and the I2C core
provides i2c_(get|put)_dma_safe_msg_buf() helpers for the host
controllers that do DMA and that is also recommendation for the
i2c_xfers() callback from the I3C core.
However due to above I3C private transfers reason I decided to implement
a bounce buffer for them and reuse the same code for the I2C transfers
too. Since this driver is currently the only I3C host controller driver
that can do DMA the implementation is done here and not in I3C core.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20231109133708.653950-5-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Host Controller goes to halt state after aborted transfer and needs to
be resumed by SW. Add this resuming to DMA mode code too.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20230921055704.1087277-13-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Fix following warning (with CONFIG_DMA_API_DEBUG) which happens with a
transfer without a data buffer.
DMA-API: i3c mipi-i3c-hci.0: device driver tries to free DMA memory it has not allocated [device address=0x0000000000000000] [size=0 bytes]
For those transfers the hci_dma_queue_xfer() doesn't create a mapping and
the DMA address pointer xfer->data_dma is not set.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20230921055704.1087277-10-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Number of software enabled Ring Bundles must be set before using them.
Otherwise Ring will not start and may be power-gated by the Host
Controller.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20230921055704.1087277-9-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Set ring start request together with ring enable in hci_dma_init(). This
causes the ring abort request in hci_dma_dequeue_xfer() will raise the
INTR_RING_OP (RING_OP_STAT in MIPI I3C HCI specification) interrupt in
the RH_INTR_STATUS register.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20230921055704.1087277-7-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Ring Abort request will timeout in case there is an error in the Host
Controller interrupt delivery or Ring Header configuration. Using BUG()
makes hard to debug those cases.
Make it less severe and turn BUG() to WARN_ON().
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20230921055704.1087277-6-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Do not loop over ring headers in hci_dma_irq_handler() that are not
allocated and enabled in hci_dma_init(). Otherwise out of bounds access
will occur from rings->headers[i] access when i >= number of allocated
ring headers.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20230921055704.1087277-5-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct hci_rings_data.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Nicolas Pitre <npitre@baylibre.com>
Cc: Len Baker <len.baker@gmx.com>
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Cc: linux-i3c@lists.infradead.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230922175019.work.129-kees@kernel.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
As noted in the "Deprecated Interfaces, Language Features, Attributes,
and Conventions" documentation [1], size calculations (especially
multiplication) should not be performed in memory allocator (or similar)
function arguments due to the risk of them overflowing. This could lead
to values wrapping around and a smaller allocation being made than the
caller was expecting. Using those allocations could lead to linear
overflows of heap memory and other misbehaviors.
So, use the struct_size() helper to do the arithmetic instead of the
argument "size + count * size" in the kzalloc() function.
[1] https://www.kernel.org/doc/html/v5.14/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments
Signed-off-by: Len Baker <len.baker@gmx.com>
Acked-by: Nicolas Pitre <npitre@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210905144054.5124-1-len.baker@gmx.com
This adds basic support for hardware implementing the MIPI I3C HCI
specification. This driver is currently limited by the capabilities
of the I3C subsystem, meaning things like scheduled commands,
auto-commands and NCM mode are not yet supported.
This supports version 1.0 of the MIPI I3C HCI spec, as well as the
imminent release of version 1.1. Support for draft version 2.0 of the
spec is also largely included with the caveat that future adjustments
to this code are likely as the spec is still a work in progress.
This is also lightly tested as actual hardware is still very scarce,
even for HCI v1.0. Hence the EXPERIMENTAL tag. Further contributions
to this driver are expected once vendor implementations and new I3C
devices become available.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-i3c/20201111220510.3622216-3-nico@fluxnic.net
