From: Will Deacon <will@kernel.org>
To: Yong Wu <yong.wu@mediatek.com>
Cc: youlin.pei@mediatek.com, devicetree@vger.kernel.org,
Nicolas Boichat <drinkcat@chromium.org>,
srv_heupstream@mediatek.com, Will Deacon <will.deacon@arm.com>,
linux-kernel@vger.kernel.org, Evan Green <evgreen@chromium.org>,
Tomasz Figa <tfiga@google.com>,
iommu@lists.linux-foundation.org,
Rob Herring <robh+dt@kernel.org>,
linux-mediatek@lists.infradead.org,
Matthias Brugger <matthias.bgg@gmail.com>,
yingjoe.chen@mediatek.com, anan.sun@mediatek.com,
Robin Murphy <robin.murphy@arm.com>,
Matthias Kaehlcke <mka@chromium.org>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v8 07/21] iommu/io-pgtable-arm-v7s: Extend MediaTek 4GB Mode
Date: Wed, 10 Jul 2019 15:36:50 +0100 [thread overview]
Message-ID: <20190710143649.w5dplhzdpi3bxp7e@willie-the-truck> (raw)
In-Reply-To: <1561774167-24141-8-git-send-email-yong.wu@mediatek.com>
On Sat, Jun 29, 2019 at 10:09:13AM +0800, Yong Wu wrote:
> MediaTek extend the arm v7s descriptor to support the dram over 4GB.
>
> In the mt2712 and mt8173, it's called "4GB mode", the physical address
> is from 0x4000_0000 to 0x1_3fff_ffff, but from EMI point of view, it
> is remapped to high address from 0x1_0000_0000 to 0x1_ffff_ffff, the
> bit32 is always enabled. thus, in the M4U, we always enable the bit9
> for all PTEs which means to enable bit32 of physical address.
>
> but in mt8183, M4U support the dram from 0x4000_0000 to 0x3_ffff_ffff
> which isn't remaped. We extend the PTEs: the bit9 represent bit32 of
> PA and the bit4 represent bit33 of PA. Meanwhile the iova still is
> 32bits.
What happens if bit4 is set in the pte for mt2712 or mt8173? Perhaps the
io-pgtable backend should be allowing oas > 32 when
IO_PGTABLE_QUIRK_ARM_MTK_4GB is set, and then enforcing that itself.
> In order to unify code, in the "4GB mode", we add the bit32 for the
> physical address manually in our driver.
>
> Correspondingly, Adding bit32 and bit33 for the PA in the iova_to_phys
> has to been moved into v7s.
>
> Regarding whether the pagetable address could be over 4GB, the mt8183
> support it while the previous mt8173 don't. thus keep it as is.
>
> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
> Reviewed-by: Evan Green <evgreen@chromium.org>
> ---
> Comparing with the previous one:
> 1). Add a new patch "iommu/mediatek: Fix iova_to_phys PA start for 4GB
> mode" before this one. Thus rebase it.
> A little difference: in the 4gb mode, we add bit32 for PA. and the PA got
> from iova_to_phys always have bit32 here, thus we should adjust it to locate
> the valid pa.
> 2). Add this code suggested from Evan.
> if (!data->plat_data->has_4gb_mode)
> data->enable_4GB = false;
> ---
> drivers/iommu/io-pgtable-arm-v7s.c | 31 ++++++++++++++++++++++++-------
> drivers/iommu/mtk_iommu.c | 29 ++++++++++++++++++-----------
> drivers/iommu/mtk_iommu.h | 1 +
> 3 files changed, 43 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c
> index 94c38db..4077822 100644
> --- a/drivers/iommu/io-pgtable-arm-v7s.c
> +++ b/drivers/iommu/io-pgtable-arm-v7s.c
> @@ -123,7 +123,9 @@
> #define ARM_V7S_TEX_MASK 0x7
> #define ARM_V7S_ATTR_TEX(val) (((val) & ARM_V7S_TEX_MASK) << ARM_V7S_TEX_SHIFT)
>
> -#define ARM_V7S_ATTR_MTK_4GB BIT(9) /* MTK extend it for 4GB mode */
> +/* MediaTek extend the two bits below for over 4GB mode */
> +#define ARM_V7S_ATTR_MTK_PA_BIT32 BIT(9)
> +#define ARM_V7S_ATTR_MTK_PA_BIT33 BIT(4)
>
> /* *well, except for TEX on level 2 large pages, of course :( */
> #define ARM_V7S_CONT_PAGE_TEX_SHIFT 6
> @@ -190,13 +192,22 @@ static dma_addr_t __arm_v7s_dma_addr(void *pages)
> static arm_v7s_iopte paddr_to_iopte(phys_addr_t paddr, int lvl,
> struct io_pgtable_cfg *cfg)
> {
> - return paddr & ARM_V7S_LVL_MASK(lvl);
> + arm_v7s_iopte pte = paddr & ARM_V7S_LVL_MASK(lvl);
> +
> + if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_4GB) {
> + if (paddr & BIT_ULL(32))
> + pte |= ARM_V7S_ATTR_MTK_PA_BIT32;
> + if (paddr & BIT_ULL(33))
> + pte |= ARM_V7S_ATTR_MTK_PA_BIT33;
> + }
> + return pte;
> }
>
> static phys_addr_t iopte_to_paddr(arm_v7s_iopte pte, int lvl,
> struct io_pgtable_cfg *cfg)
> {
> arm_v7s_iopte mask;
> + phys_addr_t paddr;
>
> if (ARM_V7S_PTE_IS_TABLE(pte, lvl))
> mask = ARM_V7S_TABLE_MASK;
> @@ -205,7 +216,14 @@ static phys_addr_t iopte_to_paddr(arm_v7s_iopte pte, int lvl,
> else
> mask = ARM_V7S_LVL_MASK(lvl);
>
> - return pte & mask;
> + paddr = pte & mask;
> + if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_4GB) {
> + if (pte & ARM_V7S_ATTR_MTK_PA_BIT32)
> + paddr |= BIT_ULL(32);
> + if (pte & ARM_V7S_ATTR_MTK_PA_BIT33)
> + paddr |= BIT_ULL(33);
> + }
> + return paddr;
I think this relies on CONFIG_PHYS_ADDR_T_64BIT, which isn't always set on
32-bit ARM.
Will
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
next prev parent reply other threads:[~2019-07-10 14:46 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-29 2:09 [PATCH v8 00/21] MT8183 IOMMU SUPPORT Yong Wu
2019-06-29 2:09 ` [PATCH v8 01/21] dt-bindings: mediatek: Add binding for mt8183 IOMMU and SMI Yong Wu
2019-06-29 2:09 ` [PATCH v8 02/21] iommu/mediatek: Use a struct as the platform data Yong Wu
2019-06-29 2:09 ` [PATCH v8 03/21] memory: mtk-smi: Use a general config_port interface Yong Wu
2019-06-29 2:09 ` [PATCH v8 04/21] memory: mtk-smi: Use a struct for the platform data for smi-common Yong Wu
2019-06-29 2:09 ` [PATCH v8 05/21] iommu/mediatek: Fix iova_to_phys PA start for 4GB mode Yong Wu
2019-06-29 2:09 ` [PATCH v8 06/21] iommu/io-pgtable-arm-v7s: Add paddr_to_iopte and iopte_to_paddr helpers Yong Wu
2019-06-29 2:09 ` [PATCH v8 07/21] iommu/io-pgtable-arm-v7s: Extend MediaTek 4GB Mode Yong Wu
2019-07-10 14:36 ` Will Deacon [this message]
2019-07-11 11:53 ` Yong Wu
2019-07-11 12:31 ` Will Deacon
2019-07-14 4:41 ` Yong Wu
2019-07-15 9:51 ` Will Deacon
2019-07-17 12:44 ` Yong Wu
2019-07-17 14:23 ` Will Deacon
2019-07-18 5:37 ` Yong Wu
2019-06-29 2:09 ` [PATCH v8 08/21] iommu/mediatek: Add bclk can be supported optionally Yong Wu
2019-06-29 2:09 ` [PATCH v8 09/21] iommu/mediatek: Add larb-id remapped support Yong Wu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190710143649.w5dplhzdpi3bxp7e@willie-the-truck \
--to=will@kernel.org \
--cc=anan.sun@mediatek.com \
--cc=devicetree@vger.kernel.org \
--cc=drinkcat@chromium.org \
--cc=evgreen@chromium.org \
--cc=iommu@lists.linux-foundation.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mediatek@lists.infradead.org \
--cc=matthias.bgg@gmail.com \
--cc=mka@chromium.org \
--cc=robh+dt@kernel.org \
--cc=robin.murphy@arm.com \
--cc=srv_heupstream@mediatek.com \
--cc=tfiga@google.com \
--cc=will.deacon@arm.com \
--cc=yingjoe.chen@mediatek.com \
--cc=yong.wu@mediatek.com \
--cc=youlin.pei@mediatek.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).