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Add a new sdhci_ops struct for Tegra210 and Tegra186 which doesn't
set the custom tuning callback used on previous SoC generations.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Program the outbound sampling trim value in tegra_sdhci_reset(). Unlike
the outbound tap value this does not depend on the signaling mode and
needs to be only programmed once.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Set the default inbound timing adjustment tap value on reset and on
non-tunable modes.
The default tap value is not programmed on tunable modes because the
tuning sequence is used instead to determine the tap value.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Parse the default inbound and outbound sampling trimmer values from
the device tree.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Add quirk to disable the card clock during configuration of the tap
value in tegra_sdhci_set_tap() and issue sdhci_reset() after value
change. This is a workaround to avoid propagation of a potential
glitch caused by setting the tap value.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Set NVQUIRK_HAS_PADCALIB on Tegra210 and Tegra186 to enable automatic
pad drive strength calibration.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Run the automatic pad calibration after voltage switching if
tegra_host->pad_calib_required is set.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Parse the pad drive strength calibration offsets from the device tree.
Program the calibration offsets in accordance with the current signaling
mode.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Disable the card clock during automatic pad drive strength calibration
and re-enable it afterwards.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Automatic pad drive strength calibration is performed on a separate pad
identical to the ones used for driving the actual bus. Power on the
calibration pad during the calibration procedure and power it off
afterwards to save power.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Configure the voltage reference used by the automatic pad drive strength
calibration procedure. The value is a magic number from the TRM.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Implement polling with 10 ms timeout for automatic pad drive strength
calibration.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Parse the pinctrl state and nvidia,only-1-8-v properties from the device
tree. Validate the pinctrl and regulator configuration before unmasking
UHS modes. Implement pad voltage state reconfiguration in the mmc
start_signal_voltage_switch() callback. Add NVQUIRK_NEEDS_PAD_CONTROL
and add set it for Tegra210 and Tegra186.
The pad configuration is done in the mmc callback because the order of
pad reconfiguration and sdhci voltage switch depend on the voltage to
which the transition occurs.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Document the Tegra SDHCI inbound and outbound sampling trimmer values.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Add bindings documentation for pad pull up and pull down offset values to be
programmed before executing automatic pad drive strength calibration.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Document the pinctrl bindings used by the SDHCI driver to reconfigure
pad voltages on controllers supporting multiple voltage levels.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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This variable is unused now after some refactoring.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Concise, but still readable.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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SDR104, HS200 and HS400 need to check for SCC error. If SCC error is
detected, retuning is necessary.
Signed-off-by: Masaharu Hayakawa <masaharu.hayakawa.ry@renesas.com>
[Niklas: update commit message]
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Checking for SCC error during retuning is unnecessary.
Signed-off-by: Masaharu Hayakawa <masaharu.hayakawa.ry@renesas.com>
[Niklas: fix small style issue]
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Add a helper to allow host drivers checking if a retune is in progress.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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for (clk = 0x80000080; new_clock >= (clock << 1); clk >>= 1)
clock <<= 1;
... is too tricky, hence I replaced with
roundup_pow_of_two(divisor) >> 2
'(clk >> 22) & 0x1' is the bit test for the 1/1 divisor, but
it is not clear. 'divisor <= 1' is easier to understand.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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renesas_sdhi_clk_start() and renesas_sdhi_clk_stop() are now only
called from renesas_sdhi_set_clock(). Merge them.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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When using DMA, if the DMA addr spans 128MB boundary, we have to split
the DMA transfer into two so that each one doesn't exceed the boundary.
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Add this hook so that it can be overridden with driver specific
implementations. We also let the original sdhci_adma_write_desc()
accept &desc so that the function can set its new value. Then export
the function so that it could be reused by driver's specific
implementations.
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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This patch adds adma_table_cnt member to struct sdhci_host to give more
flexibility to drivers to control the ADMA table count.
Default value of adma_table_cnt is set to (SDHCI_MAX_SEGS * 2 + 1).
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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In preparation to remove the node name pointer from struct device_node,
convert printf users to use the %pOFn format specifier.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hu Ziji <huziji@marvell.com>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: linux-mmc@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Allow SDHCI drivers to hook code before and after sdhci_request() by
making it externally visible.
Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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After host requests RESET_FOR_ALL action, the hardware output an
interrupt for OS and waiting for the OS to approve.
Before writing this fix, ACPI GED has handled the interrupt. But
the ACPI GED belongs to a slow process, and sometimes the handling
process time is more than 100ms(Mutex wait more than 100ms). So
drop the GED solution and add this quirk fix.
Signed-off-by: Wang Dongsheng <dongsheng.wang@hxt-semitech.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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The device specific resource can be free in free_slot after
removing host controller.
Signed-off-by: Wang Dongsheng <dongsheng.wang@hxt-semitech.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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In tuning mode of operation, when TBCTL[TB_EN] is set, eSDHC may report
one of the following errors :
1)Tuning error while running tuning operation where SYSCTL2[SAMPCLKSEL]
will not get set even when SYSCTL2[EXTN] is reset. OR
2)Data transaction error (e.g. IRQSTAT[DCE], IRQSTAT[DEBE]) during data
transaction errors.
This issue occurs when the data window sampled within eSDHC is in full
cycle. So, in that case, eSDHC is not able to find out the start and
end points of the data window and sets the sampling pointer at default
location (which is middle of the internal SD clock). If this sampling
point coincides with the data eye boundary, then it can result in the
above mentioned errors. Impact: Tuning mode of operation for SDR50,
SDR104 or HS200 speed modes may not work properly
Workaround: In case eSDHC reports tuning error or data errors in tuning
mode of operation, by add the erratum A008171 support to fix the issue.
Signed-off-by: Yinbo Zhu <yinbo.zhu@nxp.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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This patch is to add tuning error codes to
judge tuning state
Signed-off-by: Yinbo Zhu <yinbo.zhu@nxp.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Here is another TMIO MMC variant found in Socionext UniPhier SoCs.
As commit b6147490e6aa ("mmc: tmio: split core functionality, DMA and
MFD glue") said, these MMC controllers use the IP from Panasonic.
However, the MMC controller in the TMIO (Toshiba Mobile IO) MFD chip
was the first upstreamed user of this IP. The common driver code
for this IP is now called 'tmio-mmc-core' in Linux although it is a
historical misnomer.
Anyway, this driver select's MMC_TMIO_CORE to borrow the common code
from tmio-mmc-core.c
Older UniPhier SoCs (LD4, Pro4, sLD8) support the external DMA engine
like renesas_sdhi_sys_dmac.c. The difference is UniPhier SoCs use a
single DMA channel whereas Renesas chips request separate channels for
RX and TX.
Newer UniPhier SoCs (Pro5 and later) support the internal DMA engine
like renesas_sdhi_internal_dmac.c The register map is almost the same,
so I guess Renesas and Socionext use the same internal DMA hardware.
The main difference is, the register offsets are doubled for Renesas.
Renesas Socionext
SDHI UniPhier
DM_CM_DTRAN_MODE 0x820 0x410
DM_CM_DTRAN_CTRL 0x828 0x414
DM_CM_RST 0x830 0x418
DM_CM_INFO1 0x840 0x420
DM_CM_INFO1_MASK 0x848 0x424
DM_CM_INFO2 0x850 0x428
DM_CM_INFO2_MASK 0x858 0x42c
DM_DTRAN_ADDR 0x880 0x440
DM_DTRAN_ADDREX --- 0x444
This comes from the difference of host->bus_shift; 2 for Renesas SoCs,
and 1 for UniPhier SoCs. Also, the datasheet for UniPhier SoCs defines
DM_DTRAN_ADDR and DM_DTRAN_ADDREX as two separate registers.
It could be possible to factor out the DMA common code by introducing
some hooks to cope with platform quirks, but this patch does not touch
that for now.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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This SD/eMMC controller is used for UniPhier SoC family.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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tmio_mmc_set_clock() is full of quirks because different SoC vendors
extended this in different ways.
The original IP defines the divisor range 1/2 ... 1/512.
bit 7 is set: 1/512
bit 6 is set: 1/256
...
bit 0 is set: 1/4
all bits clear: 1/2
It is platform-dependent how to achieve the 1/1 clock.
I guess the TMIO-MFD variant uses the clock selector outside of this IP,
as far as I see tmio_core_mmc_clk_div() in drivers/mfd/tmio_core.c
I guess bit[7:0]=0xff is Renesas-specific extension.
Socionext (and Panasonic) uses bit 10 (CLKSEL) for 1/1. Also, newer
versions of UniPhier SoC variants use bit 16 for 1/1024.
host->clk_update() is only used by the Renesas variants, whereas
host->set_clk_div() is only used by the TMIO-MFD variants.
To cope with this mess, promote tmio_mmc_set_clock() to a new
platform hook ->set_clock(), and melt the old two hooks into it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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tmio_mmc_clk_stop(host) is equivalent to tmio_mmc_set_clock(host, 0).
This replacement is needed for the next commit.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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The JZ4725B is the first JZ SoC version that introduced a 32-bit IMASK
register, not the JZ4750.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Document the R-Car V3M (R8A77970) SoC in the R-Car SDHI bindings -- it's
the usual R-Car gen3 compatible controller with the internal DMA engine.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
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I've successfully tested eMMC on the V3H Starter Kit board and since the
R8A77970 SoC has a single SDHI core, it can't be a subject to the known RX
DMA errata.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
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Remove the stray underscore in the DM_CM_DTRAN_MODE.BUS_WIDTH register
field name and fix the typo in the comment of the #define
DTRAN_MODE_CH_NUM_CH1.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Depending on MACH_JZ4740 | MACH_JZ4780 prevent us from creating a generic
kernel that works on more than one MIPS board. Instead, we just depend on
MIPS being set.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Enable access to the RPMB on the on-board eMMC of the
Poplar board.
Signed-off-by: Igor Opaniuk <igor.opaniuk@linaro.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Document RZ/G2M (R8A774A1) SoC bindings.
Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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We need r8a774a1 to be whitelisted for SDHI to work on the RZ/G2M,
but we don't care about the revision of the SoC, so just whitelist
the generic part number.
Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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When mmc-pwrseq property is passed mmc_pwrseq_alloc() can return
-EPROBE_DEFER because driver for power sequence provider is not probed
yet. Do not show error message when this situation happens.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Add ACPI support to all IPROC SDHCI variants.
Signed-off-by: Srinath Mannam <srinath.mannam@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Vladimir Olovyannikov <vladimir.olovyannikov@broadcom.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Convert DT properties to generic device properties
so that drivers can get properties from DT or ACPI.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Srinath Mannam <srinath.mannam@broadcom.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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So:
- use 'extern' consistently for APIs
- fix weird header guard
- clarify code comments
- reorder APIs by type
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chang S. Bae <chang.seok.bae@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Markus T Metzger <markus.t.metzger@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1537312139-5580-2-git-send-email-chang.seok.bae@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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limit CPU/node NR trick
We have a special segment descriptor entry in the GDT, whose sole purpose is to
encode the CPU and node numbers in its limit (size) field. There are user-space
instructions that allow the reading of the limit field, which gives us a really
fast way to read the CPU and node IDs from the vDSO for example.
But the naming of related functionality does not make this clear, at all:
VDSO_CPU_SIZE
VDSO_CPU_MASK
__CPU_NUMBER_SEG
GDT_ENTRY_CPU_NUMBER
vdso_encode_cpu_node
vdso_read_cpu_node
There's a number of problems:
- The 'VDSO_CPU_SIZE' doesn't really make it clear that these are number
of bits, nor does it make it clear which 'CPU' this refers to, i.e.
that this is about a GDT entry whose limit encodes the CPU and node number.
- Furthermore, the 'CPU_NUMBER' naming is actively misleading as well,
because the segment limit encodes not just the CPU number but the
node ID as well ...
So use a better nomenclature all around: name everything related to this trick
as 'CPUNODE', to make it clear that this is something special, and add
_BITS to make it clear that these are number of bits, and propagate this to
every affected name:
VDSO_CPU_SIZE => VDSO_CPUNODE_BITS
VDSO_CPU_MASK => VDSO_CPUNODE_MASK
__CPU_NUMBER_SEG => __CPUNODE_SEG
GDT_ENTRY_CPU_NUMBER => GDT_ENTRY_CPUNODE
vdso_encode_cpu_node => vdso_encode_cpunode
vdso_read_cpu_node => vdso_read_cpunode
This, beyond being less confusing, also makes it easier to grep for all related
functionality:
$ git grep -i cpunode arch/x86
Also, while at it, fix "return is not a function" style sloppiness in vdso_encode_cpunode().
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chang S. Bae <chang.seok.bae@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Markus T Metzger <markus.t.metzger@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1537312139-5580-2-git-send-email-chang.seok.bae@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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