Way back in commit 4f25580fb8 ("mmc: core: changes frequency to
hs_max_dtr when selecting hs400es"), Rockchip engineers noticed that
some eMMC don't respond to SEND_STATUS commands very reliably if they're
still running at a low initial frequency. As mentioned in that commit,
JESD84-B51 P49 suggests a sequence in which the host:
1. sets HS_TIMING
2. bumps the clock ("<= 52 MHz")
3. sends further commands
It doesn't exactly require that we don't use a lower-than-52MHz
frequency, but in practice, these eMMC don't like it.
The aforementioned commit tried to get that right for HS400ES, although
it's unclear whether this ever truly worked as committed into mainline,
as other changes/refactoring adjusted the sequence in conflicting ways:
08573eaf1a ("mmc: mmc: do not use CMD13 to get status after speed mode
switch")
53e60650f7 ("mmc: core: Allow CMD13 polling when switching to HS mode
for mmc")
In any case, today we do step 3 before step 2. Let's fix that, and also
apply the same logic to HS200/400, where this eMMC has problems too.
Resolves errors like this seen when booting some RK3399 Gru/Scarlet
systems:
[ 2.058881] mmc1: CQHCI version 5.10
[ 2.097545] mmc1: SDHCI controller on fe330000.mmc [fe330000.mmc] using ADMA
[ 2.209804] mmc1: mmc_select_hs400es failed, error -84
[ 2.215597] mmc1: error -84 whilst initialising MMC card
[ 2.417514] mmc1: mmc_select_hs400es failed, error -110
[ 2.423373] mmc1: error -110 whilst initialising MMC card
[ 2.605052] mmc1: mmc_select_hs400es failed, error -110
[ 2.617944] mmc1: error -110 whilst initialising MMC card
[ 2.835884] mmc1: mmc_select_hs400es failed, error -110
[ 2.841751] mmc1: error -110 whilst initialising MMC card
Ealier versions of this patch bumped to 200MHz/HS200 speeds too early,
which caused issues on, e.g., qcom-msm8974-fairphone-fp2. (Thanks for
the report Luca!) After a second look, it appears that aligns with
JESD84 / page 45 / table 28, so we need to keep to lower (HS / 52 MHz)
rates first.
Fixes: 08573eaf1a ("mmc: mmc: do not use CMD13 to get status after speed mode switch")
Fixes: 53e60650f7 ("mmc: core: Allow CMD13 polling when switching to HS mode for mmc")
Fixes: 4f25580fb8 ("mmc: core: changes frequency to hs_max_dtr when selecting hs400es")
Cc: Shawn Lin <shawn.lin@rock-chips.com>
Link: https://lore.kernel.org/linux-mmc/11962455.O9o76ZdvQC@g550jk/
Reported-by: Luca Weiss <luca@z3ntu.xyz>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Tested-by: Luca Weiss <luca@z3ntu.xyz>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220422100824.v4.1.I484f4ee35609f78b932bd50feed639c29e64997e@changeid
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The ON Semiconductor FSA4480 is a USB Type-C port multimedia switch with
support for analog audio headsets. It allows sharing a common USB Type-C
port to pass USB2.0 signal, analog audio, sideband use wires and analog
microphone signal.
Due to lacking upstream audio support for testing, the audio muxing is
left untouched, but implementation of muxing the SBU lines is provided
as a pair of Type-C mux and switch devices. This provides the necessary
support for enabling the DisplayPort altmode on devices with this
circuit.
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220422222351.1297276-8-bjorn.andersson@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the Qualcomm platforms the USB/DP PHY handles muxing and orientation
switching of the SuperSpeed lines, but the SBU lines needs to be
connected and switched by external (to the SoC) hardware.
It's therefor necessary to be able to have the TypeC controller operate
multiple TypeC muxes and switches. Use the newly introduced indirection
object to handle this, to avoid having to taint the TypeC controllers
with knowledge about the downstream hardware configuration.
The max number of devs per indirection is set to 3, which account for
being able to mux/switch the USB HS, SS and SBU lines, as per defined
defined in the usb-c-connector binding. This number could be grown if
need arrises at a later point in time.
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220422222351.1297276-6-bjorn.andersson@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In some cases multiple connections with the same connection id
needs to be resolved from a fwnode graph.
One such example is when separate hardware is used for performing muxing
and/or orientation switching of the SuperSpeed and SBU lines in a USB
Type-C connector. In this case the connector needs to belong to a graph
with multiple matching remote endpoints, and the Type-C controller needs
to be able to resolve them both.
Add a new API that allows this kind of lookup.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220422222351.1297276-2-bjorn.andersson@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In error path of ucsi_init(), it will unregister all valid ucsi connectors,
and similar operation also happen in ucsi_unregister(),
add a common function ucsi_unregister_connectors() for two places,
inside this function, if con->wq is NULL, it will break the loop,
if other kind of error happen after con->wq allocated,
ucsi/typec related API is safe to unregister.
Also in ucsi_init(), it allocate number of (ucsi->cap.num_connectors + 1)
connectors, there is one extra as the ending,
ucsi_unregister_connectors() is safe to unregister all ucsi connectors
according ucsi->cap.num_connectors,
remove the extra one connector to save memory.
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
Link: https://lore.kernel.org/r/1650881886-25530-2-git-send-email-quic_linyyuan@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add UART_CAP_NOTEMT for UARTs that lack interrupt on TEMT but want to
use em485. Em485 framework needs to ensure not only FIFO is empty but
also that tx shift register is empty.
This approach uses Uwe Kleine-König's suggestion on simply
using/incrementing stop_tx timer rather than adding another timer. When
UART_CAP_NOTEMT is set and THRE is present w/o TEMT, stop tx timer is
reused to wait for the emptying of the shift register.
This change does not add the UART_CAP_NOTEMT define as it already exist
but is currently no-op. See 7a107b2c6b (Revert "serial: 8250: Handle
UART without interrupt on TEMT using em485") for further details.
Vicente Bergas reported that RTS is deasserted roughly one bit too
early losing stop bit tx. To address this problem, stop_delay now
accounts for one extra bit using rough formula /7 (assumes worst-case
of 2+5 bits). I suspect this glitch had to do with when THRE is getting
asserted. If FIFO is emptied already during the tx of the stop bit,
perhaps it leads to HW asserting THRE early for the normal frame time
formula to work accurately.
Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Eric Tremblay <etremblay@distech-controls.com>
Tested-by: Vicente Bergas <vicencb@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220425143410.12703-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8250 DMA tx complete path lacks calls to normal 8250 stop handling. It
does not use THRE to detect true completion of the tx and also doesn't
call __stop_tx. This leads to problems with em485 that needs to handle
RTS timing.
Instead of handling tx stop internally within 8250 dma code, enable
THRE when tx'able data runs out and tweak serial8250_handle_irq to call
only __stop_tx when uart is using DMA.
It also seems bit early to call serial8250_rpm_put_tx from there while
tx is still underway(?).
Tested-by: Vicente Bergas <vicencb@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220425143410.12703-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Struct uart_port currently stores FIFO timeout. Having character timing
information readily available is useful. Even serial core itself
determines char_time from port->timeout using inverse calculation.
Store frame_time directly into uart_port. Character time is stored in
nanoseconds to have reasonable precision with high rates. To avoid
overflow, 64-bit math is necessary.
It might be possible to determine timeout from frame_time by
multiplying it with fifosize as needed but only part of the users seem
to be protected by a lock. Thus, this patch does not pursue storing
only frame_time in uart_port.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220425143410.12703-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
DW based controllers like the one on Renesas RZ/N1 must be programmed as
flow controllers when using DMA.
* Table 11.45 of the system manual, "Flow Control Combinations", states
that using UART with DMA requires setting the DMA in the peripheral
flow controller mode regardless of the direction.
* Chapter 11.6.1.3 of the system manual, "Basic Interface Definitions",
explains that the burst size in the above case must be configured in
the peripheral's register DEST/SRC_BURST_SIZE.
Experiments shown that upon Rx timeout, the DMA transaction needed to be
manually cleared as well.
Co-developed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-9-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use device tree match data rather than multiple calls to
of_device_is_compatible() by introducing a platform data structure and
adding a quirks mask.
Provide a stub to the compatibles without quirks to simplify the
handling of the upcoming changes.
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
[<miquel.raynal@bootlin.com: Minor changes + creation of a real pdata structure]
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220422180615.9098-3-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We received a report[1] of kernel crashes when Cilium is used in XDP
mode with virtio_net after updating to newer kernels. After
investigating the reason it turned out that when using mergeable bufs
with an XDP program which adjusts xdp.data or xdp.data_meta page_to_buf()
calculates the build_skb address wrong because the offset can become less
than the headroom so it gets the address of the previous page (-X bytes
depending on how lower offset is):
page_to_skb: page addr ffff9eb2923e2000 buf ffff9eb2923e1ffc offset 252 headroom 256
This is a pr_err() I added in the beginning of page_to_skb which clearly
shows offset that is less than headroom by adding 4 bytes of metadata
via an xdp prog. The calculations done are:
receive_mergeable():
headroom = VIRTIO_XDP_HEADROOM; // VIRTIO_XDP_HEADROOM == 256 bytes
offset = xdp.data - page_address(xdp_page) -
vi->hdr_len - metasize;
page_to_skb():
p = page_address(page) + offset;
...
buf = p - headroom;
Now buf goes -4 bytes from the page's starting address as can be seen
above which is set as skb->head and skb->data by build_skb later. Depending
on what's done with the skb (when it's freed most often) we get all kinds
of corruptions and BUG_ON() triggers in mm[2]. We have to recalculate
the new headroom after the xdp program has run, similar to how offset
and len are recalculated. Headroom is directly related to
data_hard_start, data and data_meta, so we use them to get the new size.
The result is correct (similar pr_err() in page_to_skb, one case of
xdp_page and one case of virtnet buf):
a) Case with 4 bytes of metadata
[ 115.949641] page_to_skb: page addr ffff8b4dcfad2000 offset 252 headroom 252
[ 121.084105] page_to_skb: page addr ffff8b4dcf018000 offset 20732 headroom 252
b) Case of pushing data +32 bytes
[ 153.181401] page_to_skb: page addr ffff8b4dd0c4d000 offset 288 headroom 288
[ 158.480421] page_to_skb: page addr ffff8b4dd00b0000 offset 24864 headroom 288
c) Case of pushing data -33 bytes
[ 835.906830] page_to_skb: page addr ffff8b4dd3270000 offset 223 headroom 223
[ 840.839910] page_to_skb: page addr ffff8b4dcdd68000 offset 12511 headroom 223
Offset and headroom are equal because offset points to the start of
reserved bytes for the virtio_net header which are at buf start +
headroom, while data points at buf start + vnet hdr size + headroom so
when data or data_meta are adjusted by the xdp prog both the headroom size
and the offset change equally. We can use data_hard_start to compute the
new headroom after the xdp prog (linearized / page start case, the
virtnet buf case is similar just with bigger base offset):
xdp.data_hard_start = page_address + vnet_hdr
xdp.data = page_address + vnet_hdr + headroom
new headroom after xdp prog = xdp.data - xdp.data_hard_start - metasize
An example reproducer xdp prog[3] is below.
[1] https://github.com/cilium/cilium/issues/19453
[2] Two of the many traces:
[ 40.437400] BUG: Bad page state in process swapper/0 pfn:14940
[ 40.916726] BUG: Bad page state in process systemd-resolve pfn:053b7
[ 41.300891] kernel BUG at include/linux/mm.h:720!
[ 41.301801] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[ 41.302784] CPU: 1 PID: 1181 Comm: kubelet Kdump: loaded Tainted: G B W 5.18.0-rc1+ #37
[ 41.304458] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1.fc35 04/01/2014
[ 41.306018] RIP: 0010:page_frag_free+0x79/0xe0
[ 41.306836] Code: 00 00 75 ea 48 8b 07 a9 00 00 01 00 74 e0 48 8b 47 48 48 8d 50 ff a8 01 48 0f 45 fa eb d0 48 c7 c6 18 b8 30 a6 e8 d7 f8 fc ff <0f> 0b 48 8d 78 ff eb bc 48 8b 07 a9 00 00 01 00 74 3a 66 90 0f b6
[ 41.310235] RSP: 0018:ffffac05c2a6bc78 EFLAGS: 00010292
[ 41.311201] RAX: 000000000000003e RBX: 0000000000000000 RCX: 0000000000000000
[ 41.312502] RDX: 0000000000000001 RSI: ffffffffa6423004 RDI: 00000000ffffffff
[ 41.313794] RBP: ffff993c98823600 R08: 0000000000000000 R09: 00000000ffffdfff
[ 41.315089] R10: ffffac05c2a6ba68 R11: ffffffffa698ca28 R12: ffff993c98823600
[ 41.316398] R13: ffff993c86311ebc R14: 0000000000000000 R15: 000000000000005c
[ 41.317700] FS: 00007fe13fc56740(0000) GS:ffff993cdd900000(0000) knlGS:0000000000000000
[ 41.319150] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 41.320152] CR2: 000000c00008a000 CR3: 0000000014908000 CR4: 0000000000350ee0
[ 41.321387] Call Trace:
[ 41.321819] <TASK>
[ 41.322193] skb_release_data+0x13f/0x1c0
[ 41.322902] __kfree_skb+0x20/0x30
[ 41.343870] tcp_recvmsg_locked+0x671/0x880
[ 41.363764] tcp_recvmsg+0x5e/0x1c0
[ 41.384102] inet_recvmsg+0x42/0x100
[ 41.406783] ? sock_recvmsg+0x1d/0x70
[ 41.428201] sock_read_iter+0x84/0xd0
[ 41.445592] ? 0xffffffffa3000000
[ 41.462442] new_sync_read+0x148/0x160
[ 41.479314] ? 0xffffffffa3000000
[ 41.496937] vfs_read+0x138/0x190
[ 41.517198] ksys_read+0x87/0xc0
[ 41.535336] do_syscall_64+0x3b/0x90
[ 41.551637] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 41.568050] RIP: 0033:0x48765b
[ 41.583955] Code: e8 4a 35 fe ff eb 88 cc cc cc cc cc cc cc cc e8 fb 7a fe ff 48 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 28 ff ff ff ff 48 c7 44 24 30
[ 41.632818] RSP: 002b:000000c000a2f5b8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000
[ 41.664588] RAX: ffffffffffffffda RBX: 000000c000062000 RCX: 000000000048765b
[ 41.681205] RDX: 0000000000005e54 RSI: 000000c000e66000 RDI: 0000000000000016
[ 41.697164] RBP: 000000c000a2f608 R08: 0000000000000001 R09: 00000000000001b4
[ 41.713034] R10: 00000000000000b6 R11: 0000000000000212 R12: 00000000000000e9
[ 41.728755] R13: 0000000000000001 R14: 000000c000a92000 R15: ffffffffffffffff
[ 41.744254] </TASK>
[ 41.758585] Modules linked in: br_netfilter bridge veth netconsole virtio_net
and
[ 33.524802] BUG: Bad page state in process systemd-network pfn:11e60
[ 33.528617] page ffffe05dc0147b00 ffffe05dc04e7a00 ffff8ae9851ec000 (1) len 82 offset 252 metasize 4 hroom 0 hdr_len 12 data ffff8ae9851ec10c data_meta ffff8ae9851ec108 data_end ffff8ae9851ec14e
[ 33.529764] page:000000003792b5ba refcount:0 mapcount:-512 mapping:0000000000000000 index:0x0 pfn:0x11e60
[ 33.532463] flags: 0xfffffc0000000(node=0|zone=1|lastcpupid=0x1fffff)
[ 33.532468] raw: 000fffffc0000000 0000000000000000 dead000000000122 0000000000000000
[ 33.532470] raw: 0000000000000000 0000000000000000 00000000fffffdff 0000000000000000
[ 33.532471] page dumped because: nonzero mapcount
[ 33.532472] Modules linked in: br_netfilter bridge veth netconsole virtio_net
[ 33.532479] CPU: 0 PID: 791 Comm: systemd-network Kdump: loaded Not tainted 5.18.0-rc1+ #37
[ 33.532482] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1.fc35 04/01/2014
[ 33.532484] Call Trace:
[ 33.532496] <TASK>
[ 33.532500] dump_stack_lvl+0x45/0x5a
[ 33.532506] bad_page.cold+0x63/0x94
[ 33.532510] free_pcp_prepare+0x290/0x420
[ 33.532515] free_unref_page+0x1b/0x100
[ 33.532518] skb_release_data+0x13f/0x1c0
[ 33.532524] kfree_skb_reason+0x3e/0xc0
[ 33.532527] ip6_mc_input+0x23c/0x2b0
[ 33.532531] ip6_sublist_rcv_finish+0x83/0x90
[ 33.532534] ip6_sublist_rcv+0x22b/0x2b0
[3] XDP program to reproduce(xdp_pass.c):
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
SEC("xdp_pass")
int xdp_pkt_pass(struct xdp_md *ctx)
{
bpf_xdp_adjust_head(ctx, -(int)32);
return XDP_PASS;
}
char _license[] SEC("license") = "GPL";
compile: clang -O2 -g -Wall -target bpf -c xdp_pass.c -o xdp_pass.o
load on virtio_net: ip link set enp1s0 xdpdrv obj xdp_pass.o sec xdp_pass
CC: stable@vger.kernel.org
CC: Jason Wang <jasowang@redhat.com>
CC: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
CC: Daniel Borkmann <daniel@iogearbox.net>
CC: "Michael S. Tsirkin" <mst@redhat.com>
CC: virtualization@lists.linux-foundation.org
Fixes: 8fb7da9e99 ("virtio_net: get build_skb() buf by data ptr")
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20220425103703.3067292-1-razor@blackwall.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add support for queueing SKBs to the host over the transfer ring of the
relevant channel. The mhi_ep_queue_skb() API will be used by the client
networking drivers to queue the SKBs to the host over MHI bus.
The host will add ring elements to the transfer ring periodically for
the device and the device will write SKBs to the ring elements. If a
single SKB doesn't fit in a ring element (TRE), it will be placed in
multiple ring elements and the overflow event will be sent for all ring
elements except the last one. For the last ring element, the EOT event
will be sent indicating the packet boundary.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-17-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for processing the channel rings from host. For the channel
ring associated with DL channel, the xfer callback will simply invoked.
For the case of UL channel, the ring elements will be read in a buffer
till the write pointer and later passed to the client driver using the
xfer callback.
The client drivers should provide the callbacks for both UL and DL
channels during registration.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-16-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Data transfer between host and the ep device happens over the transfer
ring associated with each bi-directional channel pair. Host defines the
transfer ring by allocating memory for it. The read and write pointer
addresses of the transfer ring are stored in the channel context.
Once host places the elements in the transfer ring, it increments the
write pointer and rings the channel doorbell. Device will receive the
doorbell interrupt and will process the transfer ring elements.
This commit adds support for reading the transfer ring elements from
the transfer ring till write pointer, incrementing the read pointer and
finally sending the completion event to the host through corresponding
event ring.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-15-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for processing the command rings. Command ring is used by the
host to issue channel specific commands to the ep device. Following
commands are supported:
1. Start channel
2. Stop channel
3. Reset channel
Once the device receives the command doorbell interrupt from host, it
executes the command and generates a command completion event to the
host in the primary event ring.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-14-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for handling MHI_RESET in MHI endpoint stack. MHI_RESET will
be issued by the host during shutdown and during error scenario so that
it can recover the endpoint device without restarting the whole device.
MHI_RESET handling involves resetting the internal MHI registers, data
structures, state machines, resetting all channels/rings and setting
MHICTRL.RESET bit to 0. Additionally the device will also move to READY
state if the reset was due to SYS_ERR.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-12-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for sending the events to the host over MHI bus from the
endpoint. Following events are supported:
1. Transfer completion event
2. Command completion event
3. State change event
4. Execution Environment (EE) change event
An event is sent whenever an operation has been completed in the MHI EP
device. Event is sent using the MHI event ring and additionally the host
is notified using an IRQ if required.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-7-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for managing the MHI ring. The MHI ring is a circular queue
of data structures used to pass the information between host and the
endpoint.
MHI support 3 types of rings:
1. Transfer ring
2. Event ring
3. Command ring
All rings reside inside the host memory and the MHI EP device maps it to
the device memory using blocks like PCIe iATU. The mapping is handled in
the MHI EP controller driver itself.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-6-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for managing the Memory Mapped Input Output (MMIO) registers
of the MHI bus. All MHI operations are carried out using the MMIO registers
by both host and the endpoint device.
The MMIO registers reside inside the endpoint device memory (fixed
location based on the platform) and the address is passed by the MHI EP
controller driver during its registration.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-5-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit adds support for creating and destroying MHI endpoint devices.
The MHI endpoint devices binds to the MHI endpoint channels and are used
to transfer data between MHI host and endpoint device.
There is a single MHI EP device for each channel pair. The devices will be
created when the corresponding channels has been started by the host and
will be destroyed during MHI EP power down and reset.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-4-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit adds support for registering MHI endpoint controller drivers
with the MHI endpoint stack. MHI endpoint controller drivers manage
the interaction with the host machines (such as x86). They are also the
MHI endpoint bus master in charge of managing the physical link between
the host and endpoint device. Eventhough the MHI spec is bus agnostic,
the current implementation is entirely based on PCIe bus.
The endpoint controller driver encloses all information about the
underlying physical bus like PCIe. The registration process involves
parsing the channel configuration and allocating an MHI EP device.
Channels used in the endpoint stack follows the perspective of the MHI
host stack. i.e.,
UL - From host to endpoint
DL - From endpoint to host
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-2-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
