[PATCH v2 0/2] Enable 64-bit polling mode for R-Car Gen3 and RZ/G2+ family

[PATCH v2 0/2] Enable 64-bit polling mode for R-Car Gen3 and RZ/G2+ family

[Biju]

From: Biju Das <biju.das.jz@bp.renesas.com>

As per the RZ/{G2L,G3E} HW manual SD_BUF0 can be accessed by 16/32/64
bits. Most of the data transfer in SD/SDIO/eMMC mode is more than 8 bytes.
During testing it is found that, if the DMA buffer is not aligned to 128
bit it fallback to PIO mode. In such cases, 64-bit access is much more
efficient than the current 16-bit.

RFT->v2:
 * Collected tags
 * Fixed the build error reported by the bot.

Biju Das (2):
  mmc: tmio: Add 64-bit read/write support for SD_BUF0 in polling mode
  mmc: renesas_sdhi: Enable 64-bit polling mode

 drivers/mmc/host/renesas_sdhi_internal_dmac.c |  3 +-
 drivers/mmc/host/tmio_mmc.h                   | 14 ++++++++
 drivers/mmc/host/tmio_mmc_core.c              | 33 +++++++++++++++++++
 include/linux/platform_data/tmio.h            |  3 ++
 4 files changed, 52 insertions(+), 1 deletion(-)

-- 
2.43.0

[PATCH v2 1/2] mmc: tmio: Add 64-bit read/write support for SD_BUF0 in polling mode

[Biju]

From: Biju Das <biju.das.jz@bp.renesas.com>

As per the RZ/{G2L,G3E} HW manual SD_BUF0 can be accessed by 16/32/64
bits. Most of the data transfer in SD/SDIO/eMMC mode is more than 8 bytes.
During testing it is found that, if the DMA buffer is not aligned to 128
bit it fallback to PIO mode. In such cases, 64-bit access is much more
efficient than the current 16-bit.

Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
---
RFT->v2:
 * Collected tags
 * Fixed the buid error reported by the bot by guarding the code with
   CONFIG_64BIT.
---
 drivers/mmc/host/tmio_mmc.h        | 14 +++++++++++++
 drivers/mmc/host/tmio_mmc_core.c   | 33 ++++++++++++++++++++++++++++++
 include/linux/platform_data/tmio.h |  3 +++
 3 files changed, 50 insertions(+)

diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h
index d730b7633ae1..8cf9be9833b2 100644
--- a/drivers/mmc/host/tmio_mmc.h
+++ b/drivers/mmc/host/tmio_mmc.h
@@ -242,6 +242,20 @@ static inline void sd_ctrl_read32_rep(struct tmio_mmc_host *host, int addr,
 	ioread32_rep(host->ctl + (addr << host->bus_shift), buf, count);
 }
 
+#ifdef CONFIG_64BIT
+static inline void sd_ctrl_read64_rep(struct tmio_mmc_host *host, int addr,
+				      u64 *buf, int count)
+{
+	ioread64_rep(host->ctl + (addr << host->bus_shift), buf, count);
+}
+
+static inline void sd_ctrl_write64_rep(struct tmio_mmc_host *host, int addr,
+				       const u64 *buf, int count)
+{
+	iowrite64_rep(host->ctl + (addr << host->bus_shift), buf, count);
+}
+#endif
+
 static inline void sd_ctrl_write16(struct tmio_mmc_host *host, int addr,
 				   u16 val)
 {
diff --git a/drivers/mmc/host/tmio_mmc_core.c b/drivers/mmc/host/tmio_mmc_core.c
index 21c2f9095bac..775e0d9353d5 100644
--- a/drivers/mmc/host/tmio_mmc_core.c
+++ b/drivers/mmc/host/tmio_mmc_core.c
@@ -349,6 +349,39 @@ static void tmio_mmc_transfer_data(struct tmio_mmc_host *host,
 	/*
 	 * Transfer the data
 	 */
+#ifdef CONFIG_64BIT
+	if (host->pdata->flags & TMIO_MMC_64BIT_DATA_PORT) {
+		u64 *buf64 = (u64 *)buf;
+		u64 data = 0;
+
+		if (count >= 8) {
+			if (is_read)
+				sd_ctrl_read64_rep(host, CTL_SD_DATA_PORT,
+						   buf64, count >> 3);
+			else
+				sd_ctrl_write64_rep(host, CTL_SD_DATA_PORT,
+						    buf64, count >> 3);
+		}
+
+		/* if count was multiple of 8 */
+		if (!(count & 0x7))
+			return;
+
+		buf64 += count >> 3;
+		count %= 8;
+
+		if (is_read) {
+			sd_ctrl_read64_rep(host, CTL_SD_DATA_PORT, &data, 1);
+			memcpy(buf64, &data, count);
+		} else {
+			memcpy(&data, buf64, count);
+			sd_ctrl_write64_rep(host, CTL_SD_DATA_PORT, &data, 1);
+		}
+
+		return;
+	}
+#endif
+
 	if (host->pdata->flags & TMIO_MMC_32BIT_DATA_PORT) {
 		u32 data = 0;
 		u32 *buf32 = (u32 *)buf;
diff --git a/include/linux/platform_data/tmio.h b/include/linux/platform_data/tmio.h
index b060124ba1ae..426291713b83 100644
--- a/include/linux/platform_data/tmio.h
+++ b/include/linux/platform_data/tmio.h
@@ -47,6 +47,9 @@
 /* Some controllers have a CBSY bit */
 #define TMIO_MMC_HAVE_CBSY		BIT(11)
 
+/* Some controllers have a 64-bit wide data port register */
+#define TMIO_MMC_64BIT_DATA_PORT	BIT(12)
+
 struct tmio_mmc_data {
 	void				*chan_priv_tx;
 	void				*chan_priv_rx;
-- 
2.43.0

[PATCH v2 2/2] mmc: renesas_sdhi: Enable 64-bit polling mode

[Biju]

From: Biju Das <biju.das.jz@bp.renesas.com>

Enable 64-bit polling mode for R-Car gen3 and RZ/G2L SoCs.

Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
---
RFT->v2:
 * Collected tags
---
 drivers/mmc/host/renesas_sdhi_internal_dmac.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/renesas_sdhi_internal_dmac.c b/drivers/mmc/host/renesas_sdhi_internal_dmac.c
index 4b389e92399e..9e3ed0bcddd6 100644
--- a/drivers/mmc/host/renesas_sdhi_internal_dmac.c
+++ b/drivers/mmc/host/renesas_sdhi_internal_dmac.c
@@ -107,7 +107,8 @@ static const struct renesas_sdhi_of_data of_data_rza2 = {
 
 static const struct renesas_sdhi_of_data of_data_rcar_gen3 = {
 	.tmio_flags	= TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL |
-			  TMIO_MMC_HAVE_CBSY | TMIO_MMC_MIN_RCAR2,
+			  TMIO_MMC_HAVE_CBSY | TMIO_MMC_MIN_RCAR2 |
+			  TMIO_MMC_64BIT_DATA_PORT,
 	.capabilities	= MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
 			  MMC_CAP_CMD23 | MMC_CAP_WAIT_WHILE_BUSY,
 	.capabilities2	= MMC_CAP2_NO_WRITE_PROTECT | MMC_CAP2_MERGE_CAPABLE,
-- 
2.43.0

Re: [PATCH v2 1/2] mmc: tmio: Add 64-bit read/write support for SD_BUF0 in polling mode

[kernel test robot]

Hi Biju,

kernel test robot noticed the following build errors:

[auto build test ERROR on linus/master]
[also build test ERROR on ulf-hansson-mmc-mirror/next v6.16 next-20250729]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Biju/mmc-tmio-Add-64-bit-read-write-support-for-SD_BUF0-in-polling-mode/20250728-001022
base:   linus/master
patch link:    https://lore.kernel.org/r/20250727160731.106312-2-biju.das.jz%40bp.renesas.com
patch subject: [PATCH v2 1/2] mmc: tmio: Add 64-bit read/write support for SD_BUF0 in polling mode
config: powerpc64-randconfig-001-20250730 (https://download.01.org/0day-ci/archive/20250730/202507301421.AmWhOZBk-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project 78c460bbe8f1fc17e2e66b37edf419ccecbfecba)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250730/202507301421.AmWhOZBk-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202507301421.AmWhOZBk-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from drivers/mmc/host/uniphier-sd.c:21:
>> drivers/mmc/host/tmio_mmc.h:249:2: error: call to undeclared function 'ioread64_rep'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     249 |         ioread64_rep(host->ctl + (addr << host->bus_shift), buf, count);
         |         ^
>> drivers/mmc/host/tmio_mmc.h:255:2: error: call to undeclared function 'iowrite64_rep'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     255 |         iowrite64_rep(host->ctl + (addr << host->bus_shift), buf, count);
         |         ^
   2 errors generated.


vim +/ioread64_rep +249 drivers/mmc/host/tmio_mmc.h

   244	
   245	#ifdef CONFIG_64BIT
   246	static inline void sd_ctrl_read64_rep(struct tmio_mmc_host *host, int addr,
   247					      u64 *buf, int count)
   248	{
 > 249		ioread64_rep(host->ctl + (addr << host->bus_shift), buf, count);
   250	}
   251	
   252	static inline void sd_ctrl_write64_rep(struct tmio_mmc_host *host, int addr,
   253					       const u64 *buf, int count)
   254	{
 > 255		iowrite64_rep(host->ctl + (addr << host->bus_shift), buf, count);
   256	}
   257	#endif
   258	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v2 1/2] mmc: tmio: Add 64-bit read/write support for SD_BUF0 in polling mode

[Wolfram Sang]

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>    In file included from drivers/mmc/host/uniphier-sd.c:21:
> >> drivers/mmc/host/tmio_mmc.h:249:2: error: call to undeclared function 'ioread64_rep'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
>      249 |         ioread64_rep(host->ctl + (addr << host->bus_shift), buf, count);
>          |         ^
> >> drivers/mmc/host/tmio_mmc.h:255:2: error: call to undeclared function 'iowrite64_rep'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
>      255 |         iowrite64_rep(host->ctl + (addr << host->bus_shift), buf, count);
>          |         ^

Sigh, then the guard seems to be ARM64 after all :(


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Re: [PATCH v2 1/2] mmc: tmio: Add 64-bit read/write support for SD_BUF0 in polling mode

[Geert Uytterhoeven]

Hi Wolfram,

On Wed, 30 Jul 2025 at 11:17, Wolfram Sang <wsa-dev@sang-engineering.com> wrote:
> >    In file included from drivers/mmc/host/uniphier-sd.c:21:
> > >> drivers/mmc/host/tmio_mmc.h:249:2: error: call to undeclared function 'ioread64_rep'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
> >      249 |         ioread64_rep(host->ctl + (addr << host->bus_shift), buf, count);
> >          |         ^
> > >> drivers/mmc/host/tmio_mmc.h:255:2: error: call to undeclared function 'iowrite64_rep'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
> >      255 |         iowrite64_rep(host->ctl + (addr << host->bus_shift), buf, count);
> >          |         ^
>
> Sigh, then the guard seems to be ARM64 after all :(

ioread64_rep() is defined in include/asm-generic/io.h, and powerpc does
include that.

Perhaps drivers/mmc/host/tmio_mmc.h should just include <linux/io.h>?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

RE: [PATCH v2 1/2] mmc: tmio: Add 64-bit read/write support for SD_BUF0 in polling mode

[Biju Das]

Hi Geert/Wolfram,

> -----Original Message-----
> From: Geert Uytterhoeven <geert@linux-m68k.org>
> Sent: 30 July 2025 14:57
> Subject: Re: [PATCH v2 1/2] mmc: tmio: Add 64-bit read/write support for SD_BUF0 in polling mode
> 
> Hi Wolfram,
> 
> On Wed, 30 Jul 2025 at 11:17, Wolfram Sang <wsa-dev@sang-engineering.com> wrote:
> > >    In file included from drivers/mmc/host/uniphier-sd.c:21:
> > > >> drivers/mmc/host/tmio_mmc.h:249:2: error: call to undeclared
> > > >> function 'ioread64_rep'; ISO C99 and later do not support
> > > >> implicit function declarations [-Wimplicit-function-declaration]
> > >      249 |         ioread64_rep(host->ctl + (addr << host->bus_shift), buf, count);
> > >          |         ^
> > > >> drivers/mmc/host/tmio_mmc.h:255:2: error: call to undeclared
> > > >> function 'iowrite64_rep'; ISO C99 and later do not support
> > > >> implicit function declarations [-Wimplicit-function-declaration]
> > >      255 |         iowrite64_rep(host->ctl + (addr << host->bus_shift), buf, count);
> > >          |         ^
> >
> > Sigh, then the guard seems to be ARM64 after all :(
> 
> ioread64_rep() is defined in include/asm-generic/io.h, and powerpc does include that.
> 
> Perhaps drivers/mmc/host/tmio_mmc.h should just include <linux/io.h>?

This does not fix the issue.


biju@biju:~/lkp-tests$ COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-21 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash drivers/mmc/
Compiler will be installed in /home/biju/0day
PATH=/home/biju/0day/llvm-21.1.0-rc2-x86_64/bin:/home/biju/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin
make --keep-going CONFIG_OF_ALL_DTBS=y CONFIG_DTC=y LLVM=1 CROSS_COMPILE=powerpc64-linux- --jobs=64 KCFLAGS= -Wno-error=return-type -Wreturn-type -funsigned-char -Wundef W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash drivers/mmc/
make[1]: Entering directory '/home/biju/lkp-tests/build_dir'
  GEN     Makefile
  CALL    ../scripts/checksyscalls.sh
  CC [M]  drivers/mmc/host/tmio_mmc_core.o
  CC [M]  drivers/mmc/host/uniphier-sd.o
In file included from ../drivers/mmc/host/uniphier-sd.c:21:
../drivers/mmc/host/tmio_mmc.h:250:2: error: call to undeclared function 'ioread64_rep'; ISO C99 and later do not support implicit function declarations
      [-Wimplicit-function-declaration]
  250 |         ioread64_rep(host->ctl + (addr << host->bus_shift), buf, count);

Cheers,
Biju

RE: [PATCH v2 1/2] mmc: tmio: Add 64-bit read/write support for SD_BUF0 in polling mode

[Biju Das]

Hi Geert,

> -----Original Message-----
> From: Biju Das
> Sent: 30 July 2025 15:12
> Subject: RE: [PATCH v2 1/2] mmc: tmio: Add 64-bit read/write support for SD_BUF0 in polling mode
> 
> Hi Geert/Wolfram,
> 
> > -----Original Message-----
> > From: Geert Uytterhoeven <geert@linux-m68k.org>
> > Sent: 30 July 2025 14:57
> > Subject: Re: [PATCH v2 1/2] mmc: tmio: Add 64-bit read/write support
> > for SD_BUF0 in polling mode
> >
> > Hi Wolfram,
> >
> > On Wed, 30 Jul 2025 at 11:17, Wolfram Sang <wsa-dev@sang-engineering.com> wrote:
> > > >    In file included from drivers/mmc/host/uniphier-sd.c:21:
> > > > >> drivers/mmc/host/tmio_mmc.h:249:2: error: call to undeclared
> > > > >> function 'ioread64_rep'; ISO C99 and later do not support
> > > > >> implicit function declarations
> > > > >> [-Wimplicit-function-declaration]
> > > >      249 |         ioread64_rep(host->ctl + (addr << host->bus_shift), buf, count);
> > > >          |         ^
> > > > >> drivers/mmc/host/tmio_mmc.h:255:2: error: call to undeclared
> > > > >> function 'iowrite64_rep'; ISO C99 and later do not support
> > > > >> implicit function declarations
> > > > >> [-Wimplicit-function-declaration]
> > > >      255 |         iowrite64_rep(host->ctl + (addr << host->bus_shift), buf, count);
> > > >          |         ^
> > >
> > > Sigh, then the guard seems to be ARM64 after all :(
> >
> > ioread64_rep() is defined in include/asm-generic/io.h, and powerpc does include that.
> >
> > Perhaps drivers/mmc/host/tmio_mmc.h should just include <linux/io.h>?
> 
> This does not fix the issue.

Reason is CONFIG_GENERIC_IOMAP=y

So, ioread64_rep() is excluded.

Cheers,
Biju