Re: [PATCH] mmc: sdhci-xenon: Fix 2G limitation on AC5 SoC

From: Vadym Kochan
Date: Mon Aug 08 2022 - 05:52:51 EST

Hi Adrian,

On Mon, Aug 08, 2022 at 12:19:10PM +0300, Adrian Hunter wrote:
> On 1/08/22 12:30, Vadym Kochan wrote:
> > Hi Florian,
> >
> > On Wed, Jul 27, 2022 at 07:45:32PM +0300, Vadym Kochan wrote:
> >> Hi Florian,
> >>
> >> On Tue, Jul 26, 2022 at 10:37:46AM -0700, Florian Fainelli wrote:
> >>> On 7/26/22 10:07, Vadym Kochan wrote:
> >>>> From: Elad Nachman <enachman@xxxxxxxxxxx>
> >>>>
> >>>> There is a limitation on AC5 SoC that mmc controller
> >>>> can't have DMA access over 2G memory.
> >>>>
> >>>> Signed-off-by: Elad Nachman <enachman@xxxxxxxxxxx>
> >>>> Signed-off-by: Vadym Kochan <vadym.kochan@xxxxxxxxxxx>
> >>>> ---
> >>>> drivers/mmc/host/sdhci-xenon.c | 13 +++++++++++++
> >>>> 1 file changed, 13 insertions(+)
> >>>>
> >>>> diff --git a/drivers/mmc/host/sdhci-xenon.c b/drivers/mmc/host/sdhci-xenon.c
> >>>> index 08e838400b52..666d06b58564 100644
> >>>> --- a/drivers/mmc/host/sdhci-xenon.c
> >>>> +++ b/drivers/mmc/host/sdhci-xenon.c
> >>>> @@ -18,6 +18,7 @@
> >>>> #include <linux/of.h>
> >>>> #include <linux/pm.h>
> >>>> #include <linux/pm_runtime.h>
> >>>> +#include <linux/mm.h>
> >>>>
> >>>> #include "sdhci-pltfm.h"
> >>>> #include "sdhci-xenon.h"
> >>>> @@ -422,6 +423,8 @@ static int xenon_probe_params(struct platform_device *pdev)
> >>>> struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
> >>>> u32 sdhc_id, nr_sdhc;
> >>>> u32 tuning_count;
> >>>> + struct device_node *np = pdev->dev.of_node;
> >>>> + struct sysinfo si;
> >>>>
> >>>> /* Disable HS200 on Armada AP806 */
> >>>> if (priv->hw_version == XENON_AP806)
> >>>> @@ -450,6 +453,15 @@ static int xenon_probe_params(struct platform_device *pdev)
> >>>> }
> >>>> priv->tuning_count = tuning_count;
> >>>>
> >>>> + si_meminfo(&si);
> >>>> +
> >>>> + if (of_device_is_compatible(np, "marvell,ac5-sdhci") &&
> >>>> + ((si.totalram * si.mem_unit) > 0x80000000 /*2G*/)) {
> >>>
> >>> Why not limit the DMA mask of the device and ensure, that bounce buffers get used so you can still do DMA?
> >>>
> >>> Also, you ought to be able to describe that limitation using Device Tree (assuming this is an option) and declaring a dedicated bus node for the SDHCI controller and providing a suitable dma-ranges property, see: arch/arm/boot/dts/bcm2711.dtsi and the 'soc' node for such examples.
> >>>
> >>>
> >>
> >
> > I could use DMA only in 2 ways:
> >
> > #1 Use sdhci bounce buffer with SDMA mode
> >
> > But there was the issue that SDMA requires that SDHCI v4 mode should
> > be enabled, and when I enable it via sdhci_enable_v4_mode(host)
> > then I got error that EXT_CSD can't be recognized.
> >
> > But if I comment this line in sdhci.c:
> >
> > int sdhci_setup_host(struct sdhci_host *host)
> > {
> > ...
> >
> > /* SDMA does not support 64-bit DMA if v4 mode not set */
> > if ((host->flags & SDHCI_USE_64_BIT_DMA) && !host->v4_mode) {
> > pr_info("XXX SDMA does not support 64-bit DMA if v4 mode not set\n");
> > host->flags &= ~SDHCI_USE_SDMA;
> > }
> >
> > ...
> > }
> >
> > then everything is OK.
> >
> > #2 Use restricted-dma-pool in device-tree
> >
> > But I am not sure if it is good solution compared to #1.
> >
> > Setting only DMA mask did not help because after some time I got
> > "DMA overflow address" error stack-traces.
>
> AFAICT using a DMA mask is the correct way to solve this. If that
> reveals another issue then that must be resolved also. Can you show
> the stack traces and what kernel they are from?
>

The Linux version is next-20220808

Here is a stacktrace:

[ 40.537028] ------------[ cut here ]------------
[ 40.541698] xenon-sdhci 805c0000.sdhci: DMA addr
0x00000002ff700000+40960 overflow (mask 27fffffff, bus limit 0).
[ 40.551968] WARNING: CPU: 0 PID: 7 at kernel/dma/direct.h:103
dma_direct_map_sg+0x28c/0x2b0
[ 40.560321] Modules linked in: uio_pdrv_genirq
[ 40.564766] CPU: 0 PID: 7 Comm: kworker/0:0H Not tainted
5.19.0-next-20220808 #20
[ 40.572236] Hardware name: Marvell A0-AC5X Board (DT)
[ 40.577278] Workqueue: kblockd blk_mq_run_work_fn
[ 40.581980] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS
BTYPE=--)
[ 40.588929] pc : dma_direct_map_sg+0x28c/0x2b0
[ 40.593366] lr : dma_direct_map_sg+0x28c/0x2b0
[ 40.597801] sp : ffff80000a6eba20
[ 40.601107] x29: ffff80000a6eba20 x28: ffff000006d66080 x27:
0000000000000004
[ 40.608233] x26: 0000000000000000 x25: ffff0000004de810 x24:
0000000000000000
[ 40.615358] x23: 0000000000000002 x22: fffffc0000000000 x21:
ffff800009153360
[ 40.622484] x20: 0000000000000005 x19: 00000002ff700000 x18:
ffffffffffffffff
[ 40.629609] x17: 766f203036393034 x16: 2b30303030303766 x15:
6632303030303030
[ 40.636735] x14: 3078302072646461 x13: ffff80000a433d58 x12:
00000000000002dc
[ 40.643860] x11: 00000000000000f4 x10: ffff80000a48bd58 x9 :
ffff80000a48bd58
[ 40.650985] x8 : ffff80000a433d58 x7 : ffff80000a48bd58 x6 :
0000000000000000
[ 40.658110] x5 : 000000000000bff4 x4 : 0000000000000000 x3 :
0000000000000000
[ 40.665234] x2 : 0000000000000000 x1 : 0000000000000000 x0 :
ffff0000004add00
[ 40.672360] Call trace:
[ 40.674800] dma_direct_map_sg+0x28c/0x2b0
[ 40.678890] __dma_map_sg_attrs+0x28/0xa0
[ 40.682895] dma_map_sg_attrs+0x10/0x30
[ 40.686725] sdhci_pre_dma_transfer+0xcc/0x150
[ 40.691165] sdhci_pre_req+0x3c/0x50
[ 40.694734] mmc_blk_mq_issue_rq+0x25c/0x9d0
[ 40.698997] mmc_mq_queue_rq+0x118/0x2b0
[ 40.702912] blk_mq_dispatch_rq_list+0x19c/0x800
[ 40.707521] blk_mq_do_dispatch_sched+0x2bc/0x350
[ 40.712218] __blk_mq_sched_dispatch_requests+0x10c/0x160
[ 40.717608] blk_mq_sched_dispatch_requests+0x40/0x80
[ 40.722651] __blk_mq_run_hw_queue+0x80/0xc0
[ 40.726911] blk_mq_run_work_fn+0x24/0x30
[ 40.730913] process_one_work+0x1d0/0x320
[ 40.734919] worker_thread+0x14c/0x450
[ 40.738662] kthread+0x10c/0x110
[ 40.741885] ret_from_fork+0x10/0x20
[ 40.745457] ---[ end trace 0000000000000000 ]---
[ 40.750160] ------------[ cut here ]------------
[ 40.754770] WARNING: CPU: 0 PID: 7 at drivers/mmc/host/sdhci.c:1152
sdhci_send_command+0x7fc/0xea0
[ 40.763719] Modules linked in: uio_pdrv_genirq
[ 40.768149] CPU: 0 PID: 7 Comm: kworker/0:0H Tainted: G W
5.19.0-next-20220808 #20
[ 40.777090] Hardware name: Marvell A0-AC5X Board (DT)
[ 40.782129] Workqueue: kblockd blk_mq_run_work_fn
[ 40.786827] pstate: a04000c9 (NzCv daIF +PAN -UAO -TCO -DIT -SSBS
BTYPE=--)
[ 40.793775] pc : sdhci_send_command+0x7fc/0xea0
[ 40.798297] lr : sdhci_send_command+0x644/0xea0
[ 40.802821] sp : ffff80000a6eb980
[ 40.806127] x29: ffff80000a6eb980 x28: ffff80000a6ebcf8 x27:
0000000000000002
[ 40.813253] x26: 0000000000000000 x25: 0000000000000000 x24:
ffff0000004237c0
[ 40.820378] x23: 000000000000000b x22: ffff000006d825b8 x21:
ffff000006d82628
[ 40.827502] x20: ffff000006d825b8 x19: ffff000000423580 x18:
ffffffffffffffff
[ 40.834627] x17: 766f203036393034 x16: 2b30303030303766 x15:
6632303030303030
[ 40.841751] x14: 3078302072646461 x13: ffff80000a433d58 x12:
00000000000002dc
[ 40.848876] x11: 00000000000000f4 x10: ffff80000a48bd58 x9 :
ffff80000a48bd58
[ 40.856001] x8 : ffff80000a433d58 x7 : 0000000000000000 x6 :
ffff0000004deaf8
[ 40.863125] x5 : 0000000000000000 x4 : 0000000000000020 x3 :
0000000000000000
[ 40.870250] x2 : 0000000000020401 x1 : 0000000000000001 x0 :
00000000ffffffe4
[ 40.877374] Call trace:
[ 40.879813] sdhci_send_command+0x7fc/0xea0
[ 40.883989] sdhci_send_command_retry+0x40/0x140
[ 40.888597] sdhci_request+0x70/0xd0
[ 40.892167] __mmc_start_request+0x68/0x140
[ 40.896345] mmc_start_request+0x78/0xa0
[ 40.900260] mmc_blk_mq_issue_rq+0x284/0x9d0
[ 40.904521] mmc_mq_queue_rq+0x118/0x2b0
[ 40.908436] blk_mq_dispatch_rq_list+0x19c/0x800
[ 40.913045] blk_mq_do_dispatch_sched+0x2bc/0x350
[ 40.917741] __blk_mq_sched_dispatch_requests+0x10c/0x160
[ 40.923131] blk_mq_sched_dispatch_requests+0x40/0x80
[ 40.928173] __blk_mq_run_hw_queue+0x80/0xc0
[ 40.932435] blk_mq_run_work_fn+0x24/0x30
[ 40.936437] process_one_work+0x1d0/0x320
[ 40.940442] worker_thread+0x14c/0x450
[ 40.944184] kthread+0x10c/0x110
[ 40.947407] ret_from_fork+0x10/0x20
[ 40.950977] ---[ end trace 0000000000000000 ]---
[ 40.960738] ------------[ cut here ]------------
[ 40.965361] WARNING: CPU: 1 PID: 49 at drivers/mmc/host/sdhci.c:1152
sdhci_send_command+0x7fc/0xea0
[ 40.974403] Modules linked in: uio_pdrv_genirq
[ 40.978843] CPU: 1 PID: 49 Comm: kworker/1:1H Tainted: G W
5.19.0-next-20220808 #20
[ 40.987873] Hardware name: Marvell A0-AC5X Board (DT)
[ 40.992913] Workqueue: kblockd blk_mq_run_work_fn
[ 40.997613] pstate: a04000c9 (NzCv daIF +PAN -UAO -TCO -DIT -SSBS
BTYPE=--)
[ 41.004562] pc : sdhci_send_command+0x7fc/0xea0
[ 41.009086] lr : sdhci_send_command+0x644/0xea0
[ 41.013610] sp : ffff80000a9db980
[ 41.016915] x29: ffff80000a9db980 x28: ffff80000a9dbcf8 x27:
0000000000000002
[ 41.024041] x26: 0000000000000000 x25: 0000000000000000 x24:
ffff0000004237c0
[ 41.031166] x23: 000000000000000b x22: ffff000006d05eb8 x21:
ffff000006d05f28
[ 41.038291] x20: ffff000006d05eb8 x19: ffff000000423580 x18:
fffffc0003fde640
[ 41.045416] x17: 0000000000000000 x16: 0000000000000000 x15:
0000000000000000
[ 41.052540] x14: 0000000000000002 x13: 0000000000100000 x12:
0000000000000000
[ 41.059664] x11: 0000000000000000 x10: 0000000000000b10 x9 :
ffff80000a9db9e0
[ 41.066789] x8 : ffff000000649af0 x7 : 0000000000000000 x6 :
ffff0000004deaf8
[ 41.073914] x5 : 0000000000000000 x4 : 0000000000000020 x3 :
0000000000000000
[ 41.081039] x2 : 0000000000020401 x1 : 0000000000000001 x0 :
00000000ffffffe4
[ 41.088164] Call trace:
[ 41.090603] sdhci_send_command+0x7fc/0xea0
[ 41.094779] sdhci_send_command_retry+0x40/0x140
[ 41.099379] sdhci_request+0x70/0xd0
[ 41.102949] __mmc_start_request+0x68/0x140
[ 41.107127] mmc_start_request+0x78/0xa0
[ 41.111042] mmc_blk_mq_issue_rq+0x284/0x9d0
[ 41.115305] mmc_mq_queue_rq+0x118/0x2b0
[ 41.119221] blk_mq_dispatch_rq_list+0x19c/0x800
[ 41.123831] blk_mq_do_dispatch_sched+0x2bc/0x350
[ 41.128528] __blk_mq_sched_dispatch_requests+0x10c/0x160
[ 41.133917] blk_mq_sched_dispatch_requests+0x40/0x80
[ 41.138959] __blk_mq_run_hw_queue+0x80/0xc0
[ 41.143222] blk_mq_run_work_fn+0x24/0x30
[ 41.147223] process_one_work+0x1d0/0x320
[ 41.151230] worker_thread+0x14c/0x450
[ 41.154973] kthread+0x10c/0x110
[ 41.158195] ret_from_fork+0x10/0x20
[ 41.161766] ---[ end trace 0000000000000000 ]---
[ 41.171543] ------------[ cut here ]------------
[ 41.176169] WARNING: CPU: 1 PID: 49 at drivers/mmc/host/sdhci.c:1152
sdhci_send_command+0x7fc/0xea0
[ 41.185210] Modules linked in: uio_pdrv_genirq
[ 41.189650] CPU: 1 PID: 49 Comm: kworker/1:1H Tainted: G W
5.19.0-next-20220808 #20
[ 41.198679] Hardware name: Marvell A0-AC5X Board (DT)
[ 41.203720] Workqueue: kblockd blk_mq_run_work_fn
[ 41.208420] pstate: a04000c9 (NzCv daIF +PAN -UAO -TCO -DIT -SSBS
BTYPE=--)
[ 41.215369] pc : sdhci_send_command+0x7fc/0xea0
[ 41.219892] lr : sdhci_send_command+0x644/0xea0
[ 41.224414] sp : ffff80000a9db980
[ 41.227721] x29: ffff80000a9db980 x28: ffff80000a9dbcf8 x27:
0000000000000002
[ 41.234846] x26: 0000000000000000 x25: 0000000000000000 x24:
ffff0000004237c0
[ 41.241972] x23: 000000000000000b x22: ffff000006d001b8 x21:
ffff000006d00228
[ 41.249097] x20: ffff000006d001b8 x19: ffff000000423580 x18:
0000000000000000
[ 41.256223] x17: 0000000000000000 x16: 0000000000000000 x15:
0000000000000000
[ 41.263348] x14: 0000000000000002 x13: 0000000000100000 x12:
0000000000000000
[ 41.270473] x11: 0000000000000001 x10: 0000000000000b10 x9 :
ffff80000a9db9e0
[ 41.277598] x8 : ffff000000649af0 x7 : 0000000000000000 x6 :
ffff0000004deaf8
[ 41.284722] x5 : 0000000000000000 x4 : 0000000000000020 x3 :
0000000000000000
[ 41.291846] x2 : 0000000000020401 x1 : 0000000000000001 x0 :
00000000ffffffe4
[ 41.298971] Call trace:
[ 41.301410] sdhci_send_command+0x7fc/0xea0
[ 41.305588] sdhci_send_command_retry+0x40/0x140
[ 41.310198] sdhci_request+0x70/0xd0
[ 41.313769] __mmc_start_request+0x68/0x140
[ 41.317946] mmc_start_request+0x78/0xa0
[ 41.321862] mmc_blk_mq_issue_rq+0x284/0x9d0
[ 41.326125] mmc_mq_queue_rq+0x118/0x2b0
[ 41.330040] blk_mq_dispatch_rq_list+0x19c/0x800
[ 41.334649] blk_mq_do_dispatch_sched+0x2bc/0x350
[ 41.339346] __blk_mq_sched_dispatch_requests+0x10c/0x160
[ 41.344735] blk_mq_sched_dispatch_requests+0x40/0x80
[ 41.349779] __blk_mq_run_hw_queue+0x80/0xc0
[ 41.354040] blk_mq_run_work_fn+0x24/0x30
[ 41.358041] process_one_work+0x1d0/0x320
[ 41.362048] worker_thread+0x14c/0x450
[ 41.365791] kthread+0x10c/0x110
[ 41.369014] ret_from_fork+0x10/0x20
[ 41.372584] ---[ end trace 0000000000000000 ]---
[ 41.382383] ------------[ cut here ]------------
[ 41.387009] WARNING: CPU: 1 PID: 49 at drivers/mmc/host/sdhci.c:1152
sdhci_send_command+0x7fc/0xea0
[ 41.396051] Modules linked in: uio_pdrv_genirq
[ 41.400491] CPU: 1 PID: 49 Comm: kworker/1:1H Tainted: G W
5.19.0-next-20220808 #20
[ 41.409520] Hardware name: Marvell A0-AC5X Board (DT)
[ 41.414561] Workqueue: kblockd blk_mq_run_work_fn
[ 41.419261] pstate: a04000c9 (NzCv daIF +PAN -UAO -TCO -DIT -SSBS
BTYPE=--)
[ 41.426210] pc : sdhci_send_command+0x7fc/0xea0
[ 41.430734] lr : sdhci_send_command+0x644/0xea0
[ 41.435256] sp : ffff80000a9db980
[ 41.438562] x29: ffff80000a9db980 x28: ffff80000a9dbcf8 x27:
0000000000000002
[ 41.445687] x26: 0000000000000000 x25: 0000000000000000 x24:
ffff0000004237c0
[ 41.452812] x23: 000000000000000b x22: ffff000006d004b8 x21:
ffff000006d00528
[ 41.459937] x20: ffff000006d004b8 x19: ffff000000423580 x18:
0000000000000000
[ 41.467062] x17: 0000000000000000 x16: 0000000000000000 x15:
0000000000000000
[ 41.474187] x14: 0000000000000002 x13: 00000000000ff000 x12:
0000000000000000
[ 41.481311] x11: 0000000000000001 x10: 0000000000000b10 x9 :
ffff80000a9db9e0
[ 41.488436] x8 : ffff000000649af0 x7 : 0000000000000000 x6 :
ffff0000004deaf8
[ 41.495561] x5 : 0000000000000000 x4 : 0000000000000020 x3 :
0000000000000000
[ 41.502685] x2 : 0000000000020401 x1 : 0000000000000001 x0 :
00000000ffffffe4
[ 41.509811] Call trace:
[ 41.512250] sdhci_send_command+0x7fc/0xea0
[ 41.516427] sdhci_send_command_retry+0x40/0x140
[ 41.521035] sdhci_request+0x70/0xd0
[ 41.524607] __mmc_start_request+0x68/0x140
[ 41.528784] mmc_start_request+0x78/0xa0
[ 41.532699] mmc_blk_mq_issue_rq+0x284/0x9d0
[ 41.536961] mmc_mq_queue_rq+0x118/0x2b0
[ 41.540876] blk_mq_dispatch_rq_list+0x19c/0x800
[ 41.545485] blk_mq_do_dispatch_sched+0x2bc/0x350
[ 41.550182] __blk_mq_sched_dispatch_requests+0x10c/0x160
[ 41.555570] blk_mq_sched_dispatch_requests+0x40/0x80
[ 41.560613] __blk_mq_run_hw_queue+0x80/0xc0
[ 41.564874] blk_mq_run_work_fn+0x24/0x30
[ 41.568875] process_one_work+0x1d0/0x320
[ 41.572881] worker_thread+0x14c/0x450
[ 41.576624] kthread+0x10c/0x110
[ 41.579847] ret_from_fork+0x10/0x20
[ 41.583428] ---[ end trace 0000000000000000 ]---


> >
> >> Do I understand correctly that the swiotlb will be used in case DMA
> >> engine could not map the page in the specified range (limited by dma-ranges or
> >> dma-mask) ?
> >>
> >>>
> >>>> + host->quirks |= SDHCI_QUIRK_BROKEN_DMA;
> >>>> + host->quirks |= SDHCI_QUIRK_BROKEN_ADMA;
> >>>> + dev_info(mmc_dev(mmc), "Disabling DMA because of 2GB DMA access limit.\n");
> >>>> + }
> >>>> +
> >>>> return xenon_phy_parse_params(dev, host);
> >>>> }
> >>>>
> >>>> @@ -682,6 +694,7 @@ static const struct of_device_id sdhci_xenon_dt_ids[] = {
> >>>> { .compatible = "marvell,armada-ap807-sdhci", .data = (void *)XENON_AP807},
> >>>> { .compatible = "marvell,armada-cp110-sdhci", .data = (void *)XENON_CP110},
> >>>> { .compatible = "marvell,armada-3700-sdhci", .data = (void *)XENON_A3700},
> >>>> + { .compatible = "marvell,ac5-sdhci", .data = (void *)XENON_AP806},
> >>>> {}
> >>>> };
> >>>> MODULE_DEVICE_TABLE(of, sdhci_xenon_dt_ids);
> >>>
> >>>
> >>> --
> >>> Florian
> >>
> >> Thanks,
> >>
> >
> > Regards,
>

Thanks,
Vadym Kochan