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path: root/drivers/char/hw_random/bcm2835-rng.c (follow)
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2022-10-14hwrng: bcm2835 - use hwrng_msleep() instead of cpu_relax()Jason A. Donenfeld1-1/+1
Rather than busy looping, yield back to the scheduler and sleep for a bit in the event that there's no data. This should hopefully prevent the stalls that Mark reported: <6>[ 3.362859] Freeing initrd memory: 16196K <3>[ 23.160131] rcu: INFO: rcu_sched self-detected stall on CPU <3>[ 23.166057] rcu: 0-....: (2099 ticks this GP) idle=03b4/1/0x40000002 softirq=28/28 fqs=1050 <4>[ 23.174895] (t=2101 jiffies g=-1147 q=2353 ncpus=4) <4>[ 23.180203] CPU: 0 PID: 49 Comm: hwrng Not tainted 6.0.0 #1 <4>[ 23.186125] Hardware name: BCM2835 <4>[ 23.189837] PC is at bcm2835_rng_read+0x30/0x6c <4>[ 23.194709] LR is at hwrng_fillfn+0x71/0xf4 <4>[ 23.199218] pc : [<c07ccdc8>] lr : [<c07cb841>] psr: 40000033 <4>[ 23.205840] sp : f093df70 ip : 00000000 fp : 00000000 <4>[ 23.211404] r10: c3c7e800 r9 : 00000000 r8 : c17e6b20 <4>[ 23.216968] r7 : c17e6b64 r6 : c18b0a74 r5 : c07ccd99 r4 : c3f171c0 <4>[ 23.223855] r3 : 000fffff r2 : 00000040 r1 : c3c7e800 r0 : c3f171c0 <4>[ 23.230743] Flags: nZcv IRQs on FIQs on Mode SVC_32 ISA Thumb Segment none <4>[ 23.238426] Control: 50c5387d Table: 0020406a DAC: 00000051 <4>[ 23.244519] CPU: 0 PID: 49 Comm: hwrng Not tainted 6.0.0 #1 Link: https://lore.kernel.org/all/Y0QJLauamRnCDUef@sirena.org.uk/ Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2021-03-13hwrng: bcm2835 - add reset supportÁlvaro Fernández Rojas1-0/+10
BCM6368 devices need to reset the IPSEC controller in order to generate true random numbers. This is what BCM6368 produces without a reset: root@OpenWrt:/# cat /dev/hwrng | rngtest -c 1000 rngtest 6.10 Copyright (c) 2004 by Henrique de Moraes Holschuh This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. rngtest: starting FIPS tests... rngtest: bits received from input: 20000032 rngtest: FIPS 140-2 successes: 0 rngtest: FIPS 140-2 failures: 1000 rngtest: FIPS 140-2(2001-10-10) Monobit: 2 rngtest: FIPS 140-2(2001-10-10) Poker: 1000 rngtest: FIPS 140-2(2001-10-10) Runs: 1000 rngtest: FIPS 140-2(2001-10-10) Long run: 30 rngtest: FIPS 140-2(2001-10-10) Continuous run: 0 rngtest: input channel speed: (min=37.253; avg=320.827; max=635.783)Mibits/s rngtest: FIPS tests speed: (min=12.141; avg=15.034; max=16.428)Mibits/s rngtest: Program run time: 1336176 microseconds Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2021-03-07hwrng: bcm2835 - remove redundant null checkTian Tao1-10/+7
clk_prepare_enable() and clk_disable_unprepare() will check NULL clock parameter, so It is not necessary to add additional checks. Signed-off-by: Tian Tao <tiantao6@hisilicon.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-07-09hwrng: bcm2835 - Constify bcm2835_rng_devtype[]Rikard Falkeborn1-1/+1
bcm2835_rng_devtype[] is not modified and can be made const to allow the compiler to put it in read-only memory. Before: text data bss dec hex filename 2392 176 0 2568 a08 drivers/char/hw_random/bcm2835-rng.o After: text data bss dec hex filename 2464 104 0 2568 a08 drivers/char/hw_random/bcm2835-rng.o Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-07-09hwrng: bcm2835 - Fix W=1 unused variable warningHerbert Xu1-2/+1
This patch fixes an unused variable warning when this driver is built with CONFIG_OF=n. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-02-04treewide: remove redundant IS_ERR() before error code checkMasahiro Yamada1-1/+1
'PTR_ERR(p) == -E*' is a stronger condition than IS_ERR(p). Hence, IS_ERR(p) is unneeded. The semantic patch that generates this commit is as follows: // <smpl> @@ expression ptr; constant error_code; @@ -IS_ERR(ptr) && (PTR_ERR(ptr) == - error_code) +PTR_ERR(ptr) == - error_code // </smpl> Link: http://lkml.kernel.org/r/20200106045833.1725-1-masahiroy@kernel.org Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Cc: Julia Lawall <julia.lawall@lip6.fr> Acked-by: Stephen Boyd <sboyd@kernel.org> [drivers/clk/clk.c] Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> [GPIO] Acked-by: Wolfram Sang <wsa@the-dreams.de> [drivers/i2c] Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [acpi/scan.c] Acked-by: Rob Herring <robh@kernel.org> Cc: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-26hwrng: bcm2835 - use devm_platform_ioremap_resource() to simplify codeYueHaibing1-4/+1
Use devm_platform_ioremap_resource() to simplify the code a bit. This is detected by coccinelle. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-02-28hwrng: bcm2835 - fix probe as platform deviceJonas Gorski1-8/+10
BCM63XX (MIPS) does not use device tree, so there cannot be any of_device_id, causing the driver to fail on probe: [ 0.904564] bcm2835-rng: probe of bcm63xx-rng failed with error -22 Fix this by checking for match data only if we are probing from device tree. Fixes: 8705f24f7b57 ("hwrng: bcm2835 - Enable BCM2835 RNG to work on BCM63xx platforms") Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-16hwrng: bcm2835 - Switch to SPDX identifierStefan Wahren1-5/+2
Adopt the SPDX license identifier headers to ease license compliance management. While we are at this fix the comment style, too. Cc: Lubomir Rintel <lkundrak@v3.sk> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Eric Anholt <eric@anholt.net> Acked-by: Lubomir Rintel <lkundrak@v3.sk> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-02-22hwrng: bcm2835 - Handle deferred clock properlyStefan Wahren1-0/+2
In case the probe of the clock is deferred, we would assume it is optional. This is wrong, so defer the probe of this driver until the clock is available. Fixes: 791af4f4907a ("hwrng: bcm2835 - Manage an optional clock") Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-26hwrng: bcm2835 - Remove redundant dev_err call in bcm2835_rng_probe()weiyongjun \(A\)1-3/+1
There is a error message within devm_ioremap_resource already, so remove the dev_err call to avoid redundant error message. Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Reviewed-by: Eric Anholt <eric@anholt.net> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-29hwrng: bcm2835 - Enable BCM2835 RNG to work on BCM63xx platformsFlorian Fainelli1-1/+10
We have now incorporated all necessary functionality for the BCM63xx platforms to successfully migrate over bcm2835-rng, so add the final bits: Kconfig selection and proper platform_device device type matching to keep the same platform device name for registration to work. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-29hwrng: bcm2835 - Add Broadcom MIPS I/O accessorsFlorian Fainelli1-2/+11
Broadcom MIPS HW is always strapped to match the system-wide endian such that all I/O access to this RNG block is done with the native CPU endian, account for that. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-29hwrng: bcm2835 - Abstract I/O accessorsFlorian Fainelli1-8/+19
In preparation for allowing BCM63xx to use this driver, we abstract I/O accessors such that we can easily change those later on. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-29hwrng: bcm2835 - Manage an optional clockFlorian Fainelli1-1/+16
One of the last steps before bcm63xx-rng can be eliminated is to manage a clock during hwrng::init and hwrng::cleanup, so fetch it in the probe function, and manage it during these two steps when valid. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-29hwrng: bcm2835 - Rework interrupt maskingFlorian Fainelli1-16/+23
The interrupt masking done for Northstart Plus and Northstar (BCM5301X) is moved from being a function pointer mapped to of_device_id::data into a proper part of the hwrng::init callback. While at it, we also make the of_data be a proper structure indicating the platform specifics, since the day we need to add a second type of platform information, we would have to do that anyway. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-29hwrng: bcm2835 - Use device managed helpersFlorian Fainelli1-12/+1
Now that we have moved the RNG disabling into a hwrng::cleanup callback, we can use the device managed registration operation and remove our remove callback since it won't do anything necessary. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-29hwrng: bcm2835 - Implementation cleanup callbackFlorian Fainelli1-3/+9
We should be disabling the RNG in a hwrng::cleanup callback if we are not longer the system selected RNG, not wait until the device driver is removed. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-29hwrng: bcm2835 - Move enabling to hwrng::initFlorian Fainelli1-4/+12
We should be moving the enabling of the HWRNG into a hwrng::init callback since we can be disabled and enabled every time a different hwrng is selected in the system. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-29hwrng: bcm2835 - Define a driver private contextFlorian Fainelli1-21/+34
Instead of making hwrng::priv host the base register address, define a driver private context, make it per platform device instance and pass it down the different functions. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-29hwrng: bcm2835 - Obtain base register via resourceFlorian Fainelli1-10/+10
In preparation for consolidating bcm63xx-rng into bcm2835-rng, make sure that we obtain the base register via platform_get_resource() since we need to support the non-DT enabled MIPS-based BCM63xx DSL SoCs. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-09-07hwrng: bcm2835 - handle of_iomap failuresArvind Yadav1-2/+3
Check return value of of_iomap and handle errors correctly. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Acked-by: Eric Anholt <eric@anholt.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-06-24hwrng: bcm2835 - Add support for Broadcom BCM5301xFlorian Fainelli1-0/+1
The Broadcom BCM5301x SoCs (Northstar) utilize the same random number generator peripheral as Northstar Plus and BCM2835, but just like the NSP SoC, we need to enable the interrupt. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-31hwrng: bcm2835 - Read as much data as availableYendapally Reddy Dhananjaya Reddy1-2/+10
Read the requested number of data from the fifo Signed-off-by: Yendapally Reddy Dhananjaya Reddy <yendapally.reddy@broadcom.com> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-31hwrng: bcm2835 - Support Broadcom NSP SoC rngYendapally Reddy Dhananjaya Reddy1-4/+30
This supports the random number generator available in NSP SoC. Masks the rng interrupt for NSP. Signed-off-by: Yendapally Reddy Dhananjaya Reddy <yendapally.reddy@broadcom.com> Acked-by: Eric Anholt <eric@anholt.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-10-20char: hw_random: drop owner assignment from platform_driversWolfram Sang1-1/+0
A platform_driver does not need to set an owner, it will be populated by the driver core. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-04-11hwrng: bcm2835 - fix oops when rng h/w is accessed during registrationMatt Porter1-5/+5
Commit "d9e7972 hwrng: add randomness to system from rng sources" exposed a bug in the bcm2835-rng driver resulting in boot failure on Raspberry Pi due to the following oops: [ 28.261523] BUG: soft lockup - CPU#0 stuck for 23s! [swapper:1] [ 28.271058] [ 28.275958] CPU: 0 PID: 1 Comm: swapper Not tainted 3.14.0+ #11 [ 28.285374] task: db480000 ti: db484000 task.ti: db484000 [ 28.294279] PC is at bcm2835_rng_read+0x28/0x48 [ 28.302276] LR is at hwrng_register+0x1a8/0x238 . . . The RNG h/w is not completely initialized and enabled before hwrng_register() is called and so the bcm2835_rng_read() fails. Fix this by making the warmup/enable writes before registering the RNG source with the hwrng core. Signed-off-by: Matt Porter <mporter@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-02-07drivers/char: delete non-required instances of include <linux/init.h>Paul Gortmaker1-1/+0
None of these files are actually using any __init type directives and hence don't need to include <linux/init.h>. Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. Cc: David Airlie <airlied@linux.ie> Cc: Matt Mackall <mpm@selenic.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Kukjin Kim <kgene.kim@samsung.com> Cc: Corey Minyard <minyard@acm.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Peter Huewe <peterhuewe@gmx.de> Cc: Ashley Lai <ashley@ashleylai.com> Cc: Marcel Selhorst <tpmdd@selhorst.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-19hwrng: bcm2835: fix MODULE_LICENSE tagArnd Bergmann1-1/+1
The MODULE_LICENSE macro invocation must use either "GPL" or "GPL v2", but not "GPLv2" in order to be detected by the module loader. This fixes the allmodconfig build error: FATAL: modpost: GPL-incompatible module bcm2835-rng.ko uses GPL-only symbol 'platform_driver_unregister' Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Lubomir Rintel <lkundrak@v3.sk> Cc: Dom Cobley <popcornmix@gmail.com> Cc: Stephen Warren <swarren@wwwdotorg.org> Cc: Matt Mackall <mpm@selenic.com> Cc: linux-rpi-kernel@lists.infradead.org Cc: Herbert Xu <herbert@gondor.apana.org.au>
2013-04-25hwrng: bcm2835 - Add Broadcom BCM2835 RNG driverLubomir Rintel1-0/+113
This adds a driver for random number generator present on Broadcom BCM2835 SoC, used in Raspberry Pi and Roku 2 devices. Signed-off-by: Dom Cobley <popcornmix@gmail.com> Signed-off-by: Lubomir Rintel <lkundrak@v3.sk> Tested-by: Stephen Warren <swarren@wwwdotorg.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Stephen Warren <swarren@wwwdotorg.org> Cc: Matt Mackall <mpm@selenic.com> Cc: linux-rpi-kernel@lists.infradead.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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