[PATCH 1/3] media: rockchip: Introduce the rkvdec2 driver

[Alex Bee]

Hi,
Am 15.06.24 um 03:56 schrieb Detlev Casanova:
> This driver supports the second generation of the Rockchip Video
> decoder, also known as vdpu34x.
> It is currently only used on the RK3588(s) SoC.
> 
> There are 2 decoders on the RK3588 SoC that can work in pair to decode
> 8K video at 30 FPS but currently, only using one core at a time is
> supported.
> 
> Scheduling requests between the two cores will be implemented later.

Regarding the cores:
Did anyone of you ever check the CCU (which I tink stands for central
control unit). This feature doesn't seem to be implemented by the BSP
(neither kernel nor mpp), but the configuration workflow is described
pretty well in RK3588's TRM v 1.0 ("5.6.5 VDPU381 CCU configuration flow",
page 676): It "sounds" a lot like with this enabled you do not even haven
to care about scheduling/concurrency ... whatever for the cores - you're
just saying how much cores you want to use and the rest is done by this HW
block. I'm mentioning this early in the iterarration of this series as is
it might / would infect DT modeling. The same is true, btw., for the 4
hantro H1 encoder cores: They can also be controled by a (own) CCU.

> The core supports H264, HEVC, VP9 and AVS2 decoding but this driver
> currently only supports H264.
> 
> The driver is based on rkvdec and they may share some code in the
> future.
> The decision to make a different driver is mainly because rkvdec2 has
> more features and can work with multiple cores.
> 
> The registers are mapped in a struct in RAM using bitfields. It is IO
> copied to the HW when all values are configured.
> The decision to use such a struct instead of writing buffers one by one
> is based on the following reasons:
>   - Rockchip cores are known to misbehave when registers are not written
>     in address order,

Could you please outline what makes you come to that conclusion?

>   - Those cores also need the software to write all registers, even if
>     they are written their default values or are not related to the task
>     (this core will not start decoding some H264 frames if some VP9
>     registers are not written to 0)
>   - In the future, to support multiple cores, the scheduler could be
>     optimized by storing the precomputed registers values and copy them
>     to the HW as soos as a core becomes available.
> 
....

> +/*
> + * Constant CABAC table.
> + */
> +static const u32 rkvdec2_h264_cabac_table[928] = {
> +	0x3602f114, 0xf1144a03, 0x4a033602, 0x68e97fe4, 0x36ff35fa, 0x21173307,
> +	0x00150217, 0x31000901, 0x390576db, 0x41f54ef3, 0x310c3e01, 0x321149fc,
> +	0x2b094012, 0x431a001d, 0x68095a10, 0x68ec7fd2, 0x4ef34301, 0x3e0141f5,
> +	0x5fef56fa, 0x2d093dfa, 0x51fa45fd, 0x370660f5, 0x56fb4307, 0x3a005802,
> +	0x5ef64cfd, 0x45043605, 0x580051fd, 0x4afb43f9, 0x50fb4afc, 0x3a0148f9,
> +	0x3f002900, 0x3f003f00, 0x560453f7, 0x48f96100, 0x3e03290d, 0x4efc2d00,
> +	0x7ee560fd, 0x65e762e4, 0x52e443e9, 0x53f05eec, 0x5beb6eea, 0x5df366ee,
> +	0x5cf97fe3, 0x60f959fb, 0x2efd6cf3, 0x39ff41ff, 0x4afd5df7, 0x57f85cf7,
> +	0x36057ee9, 0x3b063c06, 0x30ff4506, 0x45fc4400, 0x55fe58f8, 0x4bff4efa,
> +	0x36024df9, 0x44fd3205, 0x2a063201, 0x3f0151fc, 0x430046fc, 0x4cfe3902,
> +	0x4004230b, 0x230b3d01, 0x180c1912, 0x240d1d0d, 0x49f95df6, 0x2e0d49fe,
> +	0x64f93109, 0x35023509, 0x3dfe3505, 0x38003800, 0x3cfb3ff3, 0x39043eff,
> +	0x390445fa, 0x3304270e, 0x4003440d, 0x3f093d01, 0x27103207, 0x34042c05,
> +	0x3cfb300b, 0x3b003bff, 0x2c052116, 0x4eff2b0e, 0x45093c00, 0x28021c0b,
> +	0x31002c03, 0x2c022e00, 0x2f003302, 0x3e022704, 0x36002e06, 0x3a023603,
> +	0x33063f04, 0x35073906, 0x37063406, 0x240e2d0b, 0x52ff3508, 0x4efd3707,
> +	0x1f162e0f, 0x071954ff, 0x031cf91e, 0x0020041c, 0x061eff22, 0x0920061e,
> +	0x1b1a131f, 0x14251e1a, 0x4611221c, 0x3b054301, 0x1e104309, 0x23122012,
> +	0x1f181d16, 0x2b122617, 0x3f0b2914, 0x40093b09, 0x59fe5eff, 0x4cfa6cf7,
> +	0x2d002cfe, 0x40fd3400, 0x46fc3bfe, 0x52f84bfc, 0x4df766ef, 0x2a001803,
> +	0x37003000, 0x47f93bfa, 0x57f553f4, 0x3a0177e2, 0x24ff1dfd, 0x2b022601,
> +	0x3a0037fa, 0x4afd4000, 0x46005af6, 0x1f051dfc, 0x3b012a07, 0x48fd3afe,
> +	0x61f551fd, 0x05083a00, 0x120e0e0a, 0x28021b0d, 0x46fd3a00, 0x55f84ffa,
> +	0x6af30000, 0x57f66af0, 0x6eee72eb, 0x6eea62f2, 0x67ee6aeb, 0x6ce96beb,
> +	0x60f670e6, 0x5bfb5ff4, 0x5eea5df7, 0x430956fb, 0x55f650fc, 0x3c0746ff,
> +	0x3d053a09, 0x320f320c, 0x36113112, 0x2e07290a, 0x310733ff, 0x29093408,
> +	0x37022f06, 0x2c0a290d, 0x35053206, 0x3f04310d, 0x45fe4006, 0x46063bfe,
> +	0x1f092c0a, 0x35032b0c, 0x260a220e, 0x280d34fd, 0x2c072011, 0x320d2607,
> +	0x2b1a390a, 0x0e0b0b0e, 0x0b120b09, 0xfe170915, 0xf120f120, 0xe927eb22,
> +	0xe129df2a, 0xf426e42e, 0xe82d1d15, 0xe630d335, 0xed2bd541, 0x091ef627,
> +	0x1b141a12, 0x52f23900, 0x61ed4bfb, 0x001b7ddd, 0xfc1f001c, 0x0822061b,
> +	0x16180a1e, 0x20161321, 0x29151f1a, 0x2f172c1a, 0x470e4110, 0x3f063c08,
> +	0x18154111, 0x171a1417, 0x171c201b, 0x2817181c, 0x1d1c2018, 0x39132a17,
> +	0x3d163516, 0x280c560b, 0x3b0e330b, 0x47f94ffc, 0x46f745fb, 0x44f642f8,
> +	0x45f449ed, 0x43f146f0, 0x46ed3eec, 0x41ea42f0, 0xfe093fec, 0xf721f71a,
> +	0xfe29f927, 0x0931032d, 0x3b241b2d, 0x23f942fa, 0x2df82af9, 0x38f430fb,
> +	0x3efb3cfa, 0x4cf842f8, 0x51fa55fb, 0x51f94df6, 0x49ee50ef, 0x53f64afc,
> +	0x43f747f7, 0x42f83dff, 0x3b0042f2, 0xf3153b02, 0xf927f221, 0x0233fe2e,
> +	0x113d063c, 0x3e2a2237, 0x00000000, 0x00000000, 0x3602f114, 0xf1144a03,
> +	0x4a033602, 0x68e97fe4, 0x36ff35fa, 0x19163307, 0x00100022, 0x290409fe,
> +	0x410276e3, 0x4ff347fa, 0x32093405, 0x360a46fd, 0x1613221a, 0x02390028,
> +	0x451a2429, 0x65f17fd3, 0x47fa4cfc, 0x34054ff3, 0x5af34506, 0x2b083400,
> +	0x52fb45fe, 0x3b0260f6, 0x57fd4b02, 0x380164fd, 0x55fa4afd, 0x51fd3b00,
> +	0x5ffb56f9, 0x4dff42ff, 0x56fe4601, 0x3d0048fb, 0x3f002900, 0x3f003f00,
> +	0x560453f7, 0x48f96100, 0x3e03290d, 0x33070f0d, 0x7fd95002, 0x60ef5bee,
> +	0x62dd51e6, 0x61e966e8, 0x63e877e5, 0x66ee6eeb, 0x50007fdc, 0x5ef959fb,
> +	0x27005cfc, 0x54f14100, 0x49fe7fdd, 0x5bf768f4, 0x37037fe1, 0x37073807,
> +	0x35fd3d08, 0x4af94400, 0x67f358f7, 0x59f75bf3, 0x4cf85cf2, 0x6ee957f4,
> +	0x4ef669e8, 0x63ef70ec, 0x7fba7fb2, 0x7fd27fce, 0x4efb42fc, 0x48f847fc,
> +	0x37ff3b02, 0x4bfa46f9, 0x77de59f8, 0x14204bfd, 0x7fd4161e, 0x3dfb3600,
> +	0x3cff3a00, 0x43f83dfd, 0x4af254e7, 0x340541fb, 0x3d003902, 0x46f545f7,
> +	0x47fc3712, 0x3d073a00, 0x19122909, 0x2b052009, 0x2c002f09, 0x2e023300,
> +	0x42fc2613, 0x2a0c260f, 0x59002209, 0x1c0a2d04, 0xf5211f0a, 0x0f12d534,
> +	0xea23001c, 0x0022e726, 0xf420ee27, 0x0000a266, 0xfc21f138, 0xfb250a1d,
> +	0xf727e333, 0xc645de34, 0xfb2cc143, 0xe3370720, 0x00000120, 0xe721241b,
> +	0xe424e222, 0xe526e426, 0xf023ee22, 0xf820f222, 0x0023fa25, 0x121c0a1e,
> +	0x291d191a, 0x48024b00, 0x230e4d08, 0x23111f12, 0x2d111e15, 0x2d122a14,
> +	0x36101a1b, 0x38104207, 0x430a490b, 0x70e974f6, 0x3df947f1, 0x42fb3500,
> +	0x50f74df5, 0x57f654f7, 0x65eb7fde, 0x35fb27fd, 0x4bf53df9, 0x5bef4df1,
> +	0x6fe76be7, 0x4cf57ae4, 0x34f62cf6, 0x3af739f6, 0x45f948f0, 0x4afb45fc,
> +	0x420256f7, 0x200122f7, 0x34051f0b, 0x43fe37fe, 0x59f84900, 0x04073403,
> +	0x0811080a, 0x25031310, 0x49fb3dff, 0x4efc46ff, 0x7eeb0000, 0x6eec7ce9,
> +	0x7ce77ee6, 0x79e569ef, 0x66ef75e5, 0x74e575e6, 0x5ff67adf, 0x5ff864f2,
> +	0x72e46fef, 0x50fe59fa, 0x55f752fc, 0x48ff51f8, 0x43014005, 0x45003809,
> +	0x45074501, 0x43fa45f9, 0x40fe4df0, 0x43fa3d02, 0x390240fd, 0x42fd41fd,
> +	0x33093e00, 0x47fe42ff, 0x46ff4bfe, 0x3c0e48f7, 0x2f002510, 0x250b2312,
> +	0x290a290c, 0x290c3002, 0x3b00290d, 0x28133203, 0x32124203, 0xfa12fa13,
> +	0xf41a000e, 0xe721f01f, 0xe425ea21, 0xe22ae227, 0xdc2dd62f, 0xef29de31,
> +	0xb9450920, 0xc042c13f, 0xd936b64d, 0xf629dd34, 0xff280024, 0x1a1c0e1e,
> +	0x370c2517, 0xdf25410b, 0xdb28dc27, 0xdf2ee226, 0xe828e22a, 0xf426e331,
> +	0xfd26f628, 0x141ffb2e, 0x2c191e1d, 0x310b300c, 0x16162d1a, 0x151b1617,
> +	0x1c1a1421, 0x221b181e, 0x27192a12, 0x460c3212, 0x470e3615, 0x2019530b,
> +	0x36153115, 0x51fa55fb, 0x51f94df6, 0x49ee50ef, 0x53f64afc, 0x43f747f7,
> +	0x42f83dff, 0x3b0042f2, 0xf6113b02, 0xf72af320, 0x0035fb31, 0x0a440340,
> +	0x392f1b42, 0x180047fb, 0x2afe24ff, 0x39f734fe, 0x41fc3ffa, 0x52f943fc,
> +	0x4cfd51fd, 0x4efa48f9, 0x44f248f4, 0x4cfa46fd, 0x3efb42fb, 0x3dfc3900,
> +	0x36013cf7, 0xf6113a02, 0xf72af320, 0x0035fb31, 0x0a440340, 0x392f1b42,
> +	0x00000000, 0x00000000, 0x3602f114, 0xf1144a03, 0x4a033602, 0x68e97fe4,
> +	0x36ff35fa, 0x101d3307, 0x000e0019, 0x3efd33f6, 0x101a63e5, 0x66e855fc,
> +	0x39063905, 0x390e49ef, 0x0a142814, 0x0036001d, 0x610c2a25, 0x75ea7fe0,
> +	0x55fc4afe, 0x390566e8, 0x58f25dfa, 0x37042cfa, 0x67f159f5, 0x391374eb,
> +	0x54043a14, 0x3f016006, 0x6af355fb, 0x4b063f05, 0x65ff5afd, 0x4ffc3703,
> +	0x61f44bfe, 0x3c0132f9, 0x3f002900, 0x3f003f00, 0x560453f7, 0x48f96100,
> +	0x3e03290d, 0x58f72207, 0x7fdc7fec, 0x5ff25bef, 0x56e754e7, 0x5bef59f4,
> +	0x4cf27fe1, 0x5af367ee, 0x500b7fdb, 0x54024c05, 0x37fa4e05, 0x53f23d04,
> +	0x4ffb7fdb, 0x5bf568f5, 0x41007fe2, 0x48004ffe, 0x38fa5cfc, 0x47f84403,
> +	0x56fc62f3, 0x52fb58f4, 0x43fc48fd, 0x59f048f8, 0x3bff45f7, 0x39044205,
> +	0x47fe47fc, 0x4aff3a02, 0x45ff2cfc, 0x33f93e00, 0x2afa2ffc, 0x35fa29fd,
> +	0x4ef74c08, 0x340953f5, 0x5afb4300, 0x48f14301, 0x50f84bfb, 0x40eb53eb,
> +	0x40e71ff3, 0x4b095ee3, 0x4af83f11, 0x1bfe23fb, 0x41035b0d, 0x4d0845f9,
> +	0x3e0342f6, 0x51ec44fd, 0x07011e00, 0x4aeb17fd, 0x7ce94210, 0xee2c2511,
> +	0x7feade32, 0x2a002704, 0x1d0b2207, 0x25061f08, 0x28032a07, 0x2b0d2108,
> +	0x2f04240d, 0x3a023703, 0x2c083c06, 0x2a0e2c0b, 0x38043007, 0x250d3404,
> +	0x3a133109, 0x2d0c300a, 0x21144500, 0xee233f08, 0xfd1ce721, 0x001b0a18,
> +	0xd434f222, 0x1113e827, 0x1d24191f, 0x0f222118, 0x4916141e, 0x1f132214,
> +	0x10132c1b, 0x240f240f, 0x15191c15, 0x0c1f141e, 0x2a18101b, 0x380e5d00,
> +	0x261a390f, 0x73e87fe8, 0x3ef752ea, 0x3b003500, 0x59f355f2, 0x5cf55ef3,
> +	0x64eb7fe3, 0x43f439f2, 0x4df647f5, 0x58f055eb, 0x62f168e9, 0x52f67fdb,
> +	0x3df830f8, 0x46f942f8, 0x4ff64bf2, 0x5cf453f7, 0x4ffc6cee, 0x4bf045ea,
> +	0x3a013afe, 0x53f74ef3, 0x63f351fc, 0x26fa51f3, 0x3afa3ef3, 0x49f03bfe,
> +	0x56f34cf6, 0x57f653f7, 0x7fea0000, 0x78e77fe7, 0x72ed7fe5, 0x76e775e9,
> +	0x71e875e6, 0x78e176e4, 0x5ef67cdb, 0x63f666f1, 0x7fce6af3, 0x39115cfb,
> +	0x5ef356fb, 0x4dfe5bf4, 0x49ff4700, 0x51f94004, 0x390f4005, 0x44004301,
> +	0x440143f6, 0x40024d00, 0x4efb4400, 0x3b053707, 0x360e4102, 0x3c052c0f,
> +	0x4cfe4602, 0x460c56ee, 0x46f44005, 0x3805370b, 0x41024500, 0x36054afa,
> +	0x4cfa3607, 0x4dfe52f5, 0x2a194dfe, 0xf710f311, 0xeb1bf411, 0xd829e225,
> +	0xd130d72a, 0xd82ee027, 0xd72ecd34, 0xed2bd934, 0xc93d0b20, 0xce3ed238,
> +	0xec2dbd51, 0x0f1cfe23, 0x01270122, 0x2614111e, 0x360f2d12, 0xf0244f00,
> +	0xef25f225, 0x0f220120, 0x19180f1d, 0x101f1622, 0x1c1f1223, 0x1c242921,
> +	0x3e152f1b, 0x1a131f12, 0x17181824, 0x1e18101b, 0x29161d1f, 0x3c102a16,
> +	0x3c0e340f, 0x7bf04e03, 0x38163515, 0x21153d19, 0x3d113213, 0x4af84efd,
> +	0x48f648f7, 0x47f44bee, 0x46fb3ff5, 0x48f24bef, 0x35f843f0, 0x34f73bf2,
> +	0xfe0944f5, 0xfc1ff61e, 0x0721ff21, 0x17250c1f, 0x4014261f, 0x25f947f7,
> +	0x31f52cf8, 0x3bf438f6, 0x43f73ff8, 0x4ff644fa, 0x4af84efd, 0x48f648f7,
> +	0x47f44bee, 0x46fb3ff5, 0x48f24bef, 0x35f843f0, 0x34f73bf2, 0xfe0944f5,
> +	0xfc1ff61e, 0x0721ff21, 0x17250c1f, 0x4014261f, 0x00000000, 0x00000000,
> +	0x3602f114, 0xf1144a03, 0x4a033602, 0x68e97fe4, 0x36ff35fa, 0x00003307,
> +	0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
> +	0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
> +	0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
> +	0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
> +	0x3f002900, 0x3f003f00, 0x560453f7, 0x48f96100, 0x3e03290d, 0x37010b00,
> +	0x7fef4500, 0x520066f3, 0x6beb4af9, 0x7fe17fe5, 0x5fee7fe8, 0x72eb7fe5,
> +	0x7bef7fe2, 0x7af073f4, 0x3ff473f5, 0x54f144fe, 0x46fd68f3, 0x5af65df8,
> +	0x4aff7fe2, 0x5bf961fa, 0x38fc7fec, 0x4cf952fb, 0x5df97dea, 0x4dfd57f5,
> +	0x3ffc47fb, 0x54f444fc, 0x41f93ef9, 0x38053d08, 0x400142fe, 0x4efe3d00,
> +	0x34073201, 0x2c00230a, 0x2d01260b, 0x2c052e00, 0x3301111f, 0x131c3207,
> +	0x3e0e2110, 0x64f16cf3, 0x5bf365f3, 0x58f65ef4, 0x56f654f0, 0x57f353f9,
> +	0x46015eed, 0x4afb4800, 0x66f83b12, 0x5f0064f1, 0x48024bfc, 0x47fd4bf5,
> +	0x45f32e0f, 0x41003e00, 0x48f12515, 0x36103909, 0x480c3e00, 0x090f0018,
> +	0x120d1908, 0x130d090f, 0x120c250a, 0x21141d06, 0x2d041e0f, 0x3e003a01,
> +	0x260c3d07, 0x270f2d0b, 0x2c0d2a0b, 0x290c2d10, 0x221e310a, 0x370a2a12,
> +	0x2e113311, 0xed1a5900, 0xef1aef16, 0xec1ce71e, 0xe525e921, 0xe428e921,
> +	0xf521ef26, 0xfa29f128, 0x11290126, 0x031bfa1e, 0xf025161a, 0xf826fc23,
> +	0x0325fd26, 0x002a0526, 0x16271023, 0x251b300e, 0x440c3c15, 0x47fd6102,
> +	0x32fb2afa, 0x3efe36fd, 0x3f013a00, 0x4aff48fe, 0x43fb5bf7, 0x27fd1bfb,
> +	0x2e002cfe, 0x44f840f0, 0x4dfa4ef6, 0x5cf456f6, 0x3cf637f1, 0x41fc3efa,
> +	0x4cf849f4, 0x58f750f9, 0x61f56eef, 0x4ff554ec, 0x4afc49fa, 0x60f356f3,
> +	0x75ed61f5, 0x21fb4ef8, 0x35fe30fc, 0x47f33efd, 0x56f44ff6, 0x61f25af3,
> +	0x5dfa0000, 0x4ff854fa, 0x47ff4200, 0x3cfe3e00, 0x4bfb3bfe, 0x3afc3efd,
> +	0x4fff42f7, 0x44034700, 0x3ef92c0a, 0x280e240f, 0x1d0c1b10, 0x24142c01,
> +	0x2a052012, 0x3e0a3001, 0x40092e11, 0x61f568f4, 0x58f960f0, 0x55f955f8,
> +	0x58f355f7, 0x4dfd4204, 0x4cfa4cfd, 0x4cff3a0a, 0x63f953ff, 0x5f025ff2,
> +	0x4afb4c00, 0x4bf54600, 0x41004401, 0x3e0349f2, 0x44ff3e04, 0x370b4bf3,
> +	0x460c4005, 0x1306060f, 0x0e0c1007, 0x0b0d0d12, 0x100f0f0d, 0x170d170c,
> +	0x1a0e140f, 0x28112c0e, 0x11182f11, 0x16191515, 0x1d161b1f, 0x320e2313,
> +	0x3f07390a, 0x52fc4dfe, 0x45095efd, 0xdd246df4, 0xe620de24, 0xe02ce225,
> +	0xf122ee22, 0xf921f128, 0x0021fb23, 0x0d210226, 0x3a0d2317, 0x001afd1d,
> +	0xf91f1e16, 0xfd22f123, 0xff240322, 0x0b200522, 0x0c220523, 0x1d1e0b27,
> +	0x271d1a22, 0x151f4213, 0x32191f1f, 0x70ec78ef, 0x55f572ee, 0x59f25cf1,
> +	0x51f147e6, 0x440050f2, 0x38e846f2, 0x32e844e9, 0xf3174af5, 0xf128f31a,
> +	0x032cf231, 0x222c062d, 0x52133621, 0x17ff4bfd, 0x2b012201, 0x37fe3600,
> +	0x40013d00, 0x5cf74400, 0x61f36af2, 0x5af45af1, 0x49f658ee, 0x56f24ff7,
> +	0x46f649f6, 0x42fb45f6, 0x3afb40f7, 0xf6153b02, 0xf81cf518, 0x031dff1c,
> +	0x1423091d, 0x430e241d, 0x00000000, 0x00000000
> +};

If I'm seeing it correctly the H.264 CABAC table it the same like for the
old rkvdec version. Boris did such a great job with constructing it based
on the standard. Please reuse it instead of pasting blobs.

> +
> +static void assemble_hw_pps(struct rkvdec2_ctx *ctx,
> +			    struct rkvdec2_h264_run *run)
> +{
> +	struct rkvdec2_h264_ctx *h264_ctx = ctx->priv;
> +	const struct v4l2_ctrl_h264_sps *sps = run->sps;
> +	const struct v4l2_ctrl_h264_pps *pps = run->pps;
> +	const struct v4l2_ctrl_h264_decode_params *dec_params = run->decode_params;
> +	const struct v4l2_h264_dpb_entry *dpb = dec_params->dpb;
> +	struct rkvdec2_h264_priv_tbl *priv_tbl = h264_ctx->priv_tbl.cpu;
> +	struct rkvdec2_sps_pps *hw_ps;
> +	dma_addr_t scaling_list_address;
> +	u32 scaling_distance;
> +	u32 i;

....

> +	__iowrite32_copy_full(rkvdec->regs + OFFSET_COMMON_REGS,
> +			      &h264_ctx->regs.common,
> +			      sizeof(h264_ctx->regs.common));
This will limit the driver to arm64 which is not great. Rockchip is still
inventing (vision) SoCs based on arm which might want to use this driver as
well. So there should be at least an alternative.

Alex