Age | Commit message (Collapse) | Author |
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use phy_read_poll_timeout() to replace the poll codes for
simplify lan87xx_read_status() function.
Suggested-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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use phy_read_poll_timeout() to replace the poll codes for
simplify the code in phy_poll_reset() function.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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use phy_read_mmd_poll_timeout() to replace the poll codes for
simplify mv3310_reset() function.
Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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use phy_read_mmd_poll_timeout() to replace the poll codes for
simplify aqr107_wait_reset_complete() function.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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use phy_read_mmd_poll_timeout() to replace the poll codes for
simplify bcm84881_wait_init() function.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Previous changes to the IP routing code have removed all the
tests for the DS_HOST route flag.
Remove the flags and all the code that sets it.
Signed-off-by: David Laight <david.laight@aculab.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Fixes gcc '-Wunused-but-set-variable' warning:
drivers/net/ethernet/cavium/thunder/nicvf_queues.c: In function nicvf_sq_free_used_descs:
drivers/net/ethernet/cavium/thunder/nicvf_queues.c:1182:12: warning:
variable tail set but not used [-Wunused-but-set-variable]
It's not used since commit 4863dea3fab01("net: Adding support for Cavium ThunderX network controller"),
so remove it.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zheng zengkai <zhengzengkai@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Packet trap groups are now explicitly registered by drivers and not
implicitly registered when the packet traps are registered. Therefore,
there is no need to encode entire group structure the trap is associated
with inside the trap structure.
Instead, only pass the group identifier. Refer to it as initial group
identifier, as future patches will allow user space to move traps
between groups.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Use the previously added API to explicitly register / unregister
supported packet trap groups. This is in preparation for future patches
that will enable drivers to pass additional group attributes, such as
associated policer identifier.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Use the previously added API to explicitly register / unregister
supported packet trap groups. This is in preparation for future patches
that will enable drivers to pass additional group attributes, such as
associated policer identifier.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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So far only the reset bit it set, but the handler executing the reset
is not scheduled. Therefore nothing will happen until some other action
schedules the handler. Improve this by ensuring that the handler is
scheduled.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The current implementation makes the implicit assumption that if a bit
is set, then the work is scheduled already. Remove the need for this
implicit assumption and call schedule_work() always. It will check
internally whether the work is scheduled already.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Currently rtl_task() is designed to handle a large number of tasks.
However we have just one, so we can remove some overhead.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Factor out setting GPHY 10M to new helper rtl8168g_enable_gphy_10m.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/next-queue
Jeff Kirsher says:
====================
100GbE Intel Wired LAN Driver Updates 2020-03-21
Implement basic support for the devlink interface in the ice driver.
Additionally pave some necessary changes for adding a devlink region that
exposes the NVM contents.
This series first contains 5 patches for enabling and implementing full NVM
read access via the ETHTOOL_GEEPROM interface. This includes some cleanup of
endian-types, a new function for reading from the NVM and Shadow RAM as a flat
addressable space, a function to calculate the available flash size during
load, and a change to how some of the NVM version fields are stored in the
ice_nvm_info structure.
Following this is 3 patches for implementing devlink support. First, one patch
which implements the basic framework and introduces the ice_devlink.c file.
Second, a patch to implement basic .info_get support. Finally, a patch which
reads the device PBA identifier and reports it as the `board.id` value in the
.info_get response.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch removes wrapper fn()s around mutex_init/lock/unlock.
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Removed MODULE_VERSION and fixed MODULE_AUTHOR.
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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With MTU sized receive buffers it is not expected to have CQE_RX
with multiple receive buffer pointers. But since same physcial link
is shared by PF and it's VFs, the max receive packet configured
at link could be morethan MTU. Hence there is a chance of receiving
plts morethan MTU which then gets DMA'ed into multiple buffers
and notified in a single CQE_RX. This patch treats such pkts as errors
and frees up receive buffers pointers back to hardware.
Also on the transmit side this patch sets SMQ MAXLEN to max value to avoid
HW length errors for the packets whose size > MTU, eg due to path MTU.
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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VF shares physical link with PF. Admin function (AF) sends
notification to PF whenever a link change event happens. PF
has to forward the same notification to each of the enabled VF.
PF traps START/STOP_RX messages sent by VF to AF to keep track of
VF's enabled/disabled state.
Signed-off-by: Tomasz Duszynski <tduszynski@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Added ethtool support for VF devices for
- Driver stats, Tx/Rx perqueue stats
- Set/show Rx/Tx queue count
- Set/show Rx/Tx ring sizes
- Set/show IRQ coalescing parameters
- RSS configuration etc
It's the PF which owns the interface, hence VF
cannot display underlying CGX interface stats.
Except for this rest ethtool support reuses PF's
APIs.
Signed-off-by: Tomasz Duszynski <tduszynski@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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On OcteonTx2 silicon there two two types VFs, VFs that share the
physical link with their parent SR-IOV PF and the VFs which work
in pairs using internal HW loopback channels (LBK). Except for the
underlying Rx/Tx channel mapping from netdev functionality perspective
they are almost identical. This patch adds netdev driver support
for these VFs.
Unlike it's parent PF a VF cannot directly communicate with admin
function (AF) and it has to go through PF for the same. The mailbox
communication with AF works like 'VF <=> PF <=> AF'.
Also functionality wise VF and PF are identical, hence to avoid code
duplication PF driver's APIs are resued here for HW initialization,
packet handling etc etc ie almost everything. For VF driver to compile
as module exported few of the existing PF driver APIs.
Signed-off-by: Subbaraya Sundeep <sbhatta@marvell.com>
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: Tomasz Duszynski <tduszynski@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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When FLR is initiated for a VF (PCI function level reset),
the parent PF gets a interrupt. PF then sends a message to
admin function (AF), which then cleanups all resources attached
to that VF.
Also handled IRQs triggered when master enable bit is cleared
or set for VFs. This handler just clears the transaction pending
ie TRPEND bit.
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Added 'sriov_configure' to enable/disable virtual functions (VFs).
Also added handling of mailbox messages from these VFs.
Admin function (AF) is the only one with all priviliges to configure
HW, alloc resources etc etc, PFs and it's VFs have to request AF
via mbox for all their needs. But unlike PFs, their VFs cannot
send a mbox request directly. A VF shares a mailbox region with
it's parent PF, so VF sends a mailbox msg to PF and then PF forwards
it to AF. Then AF after processing sends response to PF which it
again forwards to VF.
This patch adds support for this 'VF <=> PF <=> AF' mailbox
communication.
Signed-off-by: Tomasz Duszynski <tduszynski@marvell.com>
Signed-off-by: Subbaraya Sundeep <sbhatta@marvell.com>
Signed-off-by: Christina Jacob <cjacob@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Now that phylib notifies the user of a downshift we can remove
this functionality from the driver.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Now that phylib notifies the user of a downshift we can remove
this functionality from the driver.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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So far PHY drivers have to check whether a downshift occurred to be
able to notify the user. To make life of drivers authors a little bit
easier move the downshift notification to phylib. phy_check_downshift()
compares the highest mutually advertised speed with the actual value
of phydev->speed (typically read by the PHY driver from a
vendor-specific register) to detect a downshift.
v2:
- Add downshift hint to phy_print_status
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Restart AutoNeg if we didn't get a valid result from previous run.
Signed-off-by: Jose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Set XPCS Link as down when AutoNeg is enabled but it didn't finish with
success.
Signed-off-by: Jose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Reset the XPCS upon probe stage so that we start it from well known
state.
Signed-off-by: Jose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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For 10GKR rate, when link errors are found we need to return fault
status so that XPCS is correctly resumed.
Signed-off-by: Jose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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When building arm32 allyesconfig:
ld.lld: error: undefined symbol: __aeabi_uldivmod
>>> referenced by spectrum_cnt.c
>>> net/ethernet/mellanox/mlxsw/spectrum_cnt.o:(mlxsw_sp_counter_resources_register) in archive drivers/built-in.a
>>> did you mean: __aeabi_uidivmod
>>> defined in: arch/arm/lib/lib.a(lib1funcs.o)
pool_size and bank_size are u64; use div64_u64 so that 32-bit platforms
do not error.
Fixes: ab8c4cc60420 ("mlxsw: spectrum_cnt: Move config validation along with resource register")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Commit 53eca1f3479f ("net: rename flow_action_hw_stats_types* ->
flow_action_hw_stats*") renamed just the flow action types and
helpers. For consistency rename variables, enums, struct members
and UAPI too (note that this UAPI was not in any official release,
yet).
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This is a dual copper PHY with support for MII/GMII/RGMII on MAC side,
as well as a bunch of other features such as SyncE and Ring Resiliency.
I haven't tested interrupts and WoL, but I am confident that they work
since support is already present in the driver and the register map is
no different for this PHY.
PHY statistics work, PHY tunables appear to work, suspend/resume works.
Signed-off-by: Wes Li <wes.li@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The driver appears to be secretly enabling the RX clock skew
irrespective of PHY interface type, which is generally considered a big
no-no.
Make them configurable instead, and add TX internal delays when
necessary too.
While at it, configure a more canonical clock skew of 2.0 nanoseconds
than the current default of 1.1 ns.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The helper for configuring the pinout of the MII side of the PHY should
do so irrespective of whether RGMII delays are used or not. So accept
the ID, TXID and RXID variants as well, not just the no-delay RGMII
variant.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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There is nothing RX-specific about these clock skew values. So remove
"RX" from the name in preparation for the next patch where TX delays are
also going to be configured.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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commit ed0a72e0de16 ("net/freescale: Clean drivers from static versions")
leave behind this, remove it .
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Kernel TLS forms TLS header in kernel during encryption and removes
while decryption before giving packet back to user application. The
similar logic is introduced in chtls code as well.
v1->v2:
- tls_proccess_cmsg() uses tls_handle_open_record() which is not required
in TOE-TLS. Don't mix TOE with other TLS types.
Signed-off-by: Vinay Kumar Yadav <vinay.yadav@chelsio.com>
Signed-off-by: Rohit Maheshwari <rohitm@chelsio.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Fix the warning reported by sparse as:
drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c:4819:17: sparse: sparse: cast from restricted __le16
drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c:4892:17: sparse: sparse: cast from restricted __le16
Signed-off-by: Chris Chiu <chiu@endlessm.com>
Reported-by: kbuild test robot <lkp@intel.com>
Acked-by: Jes Sorensen <jes@trained-monkey.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200319064341.49500-1-chiu@endlessm.com
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Add mt7615_mcu_wait_response declaration in mt7615.h since it will be
reused adding usb support to mt7615 driver
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 044a43256a35 ("mt76: mt7615: introduce mt7615_mcu_wait_response")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/d341335a636b6ccd088dd2cfeec2d296eb4dc8c7.1584534454.git.lorenzo@kernel.org
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Fix cid field endianness in unified mt7615_uni_txd header
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 323d7daad363 ("mt76: mt7615: introduce uni cmd command types")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/2447b399d3c63885d43f65ba988c057fa96f5236.1584534454.git.lorenzo@kernel.org
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Convert fields in mt7663_fw_trailer and mt7663_fw_buf to little-endian
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: f40ac0f3d3c0 ("mt76: mt7615: introduce mt7663e support")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/d14dfd7cd91a4dda8c5dcd03e8a70ff11314182e.1584534454.git.lorenzo@kernel.org
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After MAC switched power, the hardware's RF registers will have
its default value, but the default value for path B is incorrect.
So, load RF path B first, to decrease the period between MAC on
and RF path B config.
By test, if we load path A first, then there's ~300ms that the
path B is incorrect, it could lead to BT coex's A2DP glitch.
But if we configure path B first, there will only have ~3ms,
significantly lower possibility to have A2DP sound glitch.
Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200318095224.12940-1-yhchuang@realtek.com
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Driver used to kick off every TX packets, that will waste some
time while we can do better to kick off the TX packets once after
they are all prepared to be transmitted.
For PCI, it uses DMA engine to transfer the SKBs to the device,
and the transition of the state of the DMA engine could be a cost.
Driver can save some time to kick off multiple SKBs once so that
the DMA engine will have only one transition.
So, split rtw_hci_ops::tx() to rtw_hci_ops::tx_write() and
rtw_hci_ops::tx_kick_off() to explicitly kick the SKBs off after
they are written to the prepared buffer. For packets come from
ieee80211_ops::tx(), write one and then kick it off immediately.
For packets queued in TX queue, which come from
ieee80211_ops::wake_tx_queue(), we can dequeue them, write them
to the buffer, and then kick them off together.
Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200312080852.16684-6-yhchuang@realtek.com
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Add a macro TRX_BD_IDX_MASK for access the TX/RX BD indexes.
The hardware has only 12 bits for TX/RX BD indexes, we should not
initialize a TX/RX ring or access the TX/RX BD index with a length
that is larger than TRX_BD_IDX_MASK.
Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200312080852.16684-5-yhchuang@realtek.com
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Each device has only one reserved page shared with all of the
vifs, so it seems not reasonable to pass vif as one of the
arguments to rtw_fw_download_rsvd_page(). If driver is going
to run more than one vif, the content of reserved page could
not be built for all of the vifs.
To fix it, let each vif maintain its own reserved page list,
and build the final reserved page to download to the firmware
from all of the vifs. Hence driver should add reserved pages
to each vif according to the vif->type when adding the vif.
For station mode, add reserved page with rtw_add_rsvd_page_sta().
If the station mode is going to suspend in PNO (net-detect)
mode, remove the reserved pages used for normal mode, and add
new one for wowlan mode with rtw_add_rsvd_page_pno().
For beacon mode, only beacon is required to be added using
rtw_add_rsvd_page_bcn().
This would make the code flow simpler as we don't need to
add reserved pages when vif is running, just add/remove them
when ieee80211_ops::[add|remove]_interface.
When driver is going to download the reserved page, it will
collect pages from all of the vifs, this list is maintained
by rtwdev, with build_list as the pages' member. That way, we
can still build a list of reserved pages to be downloaded.
Also we can get the location of the pages from the list that
is maintained by rtwdev.
The biggest problem is that the first page should always be
beacon, if other type of reserved page is put in the first
page, the tx descriptor and offset could be wrong.
But station mode vif does not add beacon into its list, so
we need to add a dummy page in front of the list, to make
sure other pages will not be put in the first page. As the
dummy page is allocated when building the list, we must free
it before building a new list of reserved pages to firmware.
Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200312080852.16684-4-yhchuang@realtek.com
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Extract skb allocation routines for rsvd_page and h2c.
These routines should also be used by USB and SDIO.
This should not change the logic at all.
memset() for pkt_info is unnecessary, just declare as {0}.
Also skb_put()/memcpy() can be replaced by skb_put_data().
Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200312080852.16684-3-yhchuang@realtek.com
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This driver generally only needs to ensure that
(a) it doesn't try to process TX interrupts at the same time as
power-save operations (and similar)
(b) the device interrupt gets disabled while we're still handling the
last set of interrupts
For (a), all the operations (e.g., PS transitions, packet handling)
happens in non-atomic contexts (e.g., threaded IRQ).
For (b), we only need mutual exclusion for brief sections (i.e., while
we're actually manipulating the interrupt mask/status).
So, we can introduce a separate lock for handling (b), disabling IRQs
while we do it. For (a), we can demote the locking to BH only, now that
(b) (the only steps done in atomic context) and that has its own lock.
This helps reduce the amount of time this driver spends with IRQs off.
Notably, transitioning out of power-save modes can take >3 milliseconds,
and this transition is done under the protection of 'irq_lock'.
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200312080852.16684-2-yhchuang@realtek.com
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The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200319230617.GA15035@embeddedor.com
|
|
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200319230525.GA14835@embeddedor.com
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