- 16 Jul, 2020 1 commit
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Martin Sperl authored
Setting spi_transfer->effective_speed_hz in transfer_one so that it can get used in cs_change_delay configured with delay as a muliple of SPI clock cycles. Signed-off-by:
Martin Sperl <kernel@martin.sperl.org> Signed-off-by:
Marc Kleine-Budde <mkl@pengutronix.de> Link: https://lore.kernel.org/r/20200709074120.110069-2-mkl@pengutronix.deSigned-off-by:
Mark Brown <broonie@kernel.org>
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- 15 Jul, 2020 1 commit
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Qing Zhang authored
Convert clk_enable() to clk_prepare_enable() and clk_disable() to clk_disable_unprepare() respectively in the spi-omap-uwire.c. Signed-off-by:
Qing Zhang <zhangqing@loongson.cn> Link: https://lore.kernel.org/r/1594790807-32319-1-git-send-email-zhangqing@loongson.cnSigned-off-by:
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- 14 Jul, 2020 6 commits
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Mark Brown authored
Hi, This series adds support for octal DTR flashes in the spi-nor framework, and then adds hooks for the Cypress Semper and Mircom Xcella flashes to allow running them in octal DTR mode. This series assumes that the flash is handed to the kernel in Legacy SPI mode. Tested on TI J721e EVM with 1-bit ECC on the Cypress flash. Changes in v10: - Rebase on latest linux-next/master. Drop a couple patches that made it in the previous release. - Move the code that sets 20 dummy cycles for MT35XU512ABA to its octal enable function. This way, if the controller doesn't support 8D mode 20 dummy cycles won't be used. Changes in v9: - Do not use '& 0xff' to get the opcode LSB in spi-mxic and spi-zynq-qspi. The cast to u8 will do that anyway. - Do not use if (opcode) as a check for whether the command phase exists in spi-zynq-qspi because the opcode 0 can be valid. Use the new cmd.nbytes instead. Changes in v8: - Move controller changes in spi-mxic to the commit which introduces 2-byte opcodes to avoid problems when bisecting. - Replace usage of sizeof(op->cmd.opcode) with op->cmd.nbytes. - Extract opcode in spi-zynq-qspi instead of using &op->cmd.opcode. Changes in v7: - Reject ops with more than 1 command byte in spi_mem_default_supports_op(). - Reject ops with more than 1 command byte in atmel and mtk controllers. - Reject ops with 0 command bytes in spi_mem_check_op(). - Set cmd.nbytes to 1 when using SPI_MEM_OP_CMD(). - Avoid endianness problems in spi-mxic. Changes in v6: - Instead of hard-coding 8D-8D-8D Fast Read dummy cycles to 20, find them out from the Profile 1.0 table. Changes in v5: - Do not enable stateful X-X-X modes if the reset line is broken. - Instead of setting SNOR_READ_HWCAPS_8_8_8_DTR from Profile 1.0 table parsing, do it in spi_nor_info_init_params() instead based on the SPI_NOR_OCTAL_DTR_READ flag instead. - Set SNOR_HWCAPS_PP_8_8_8_DTR in s28hs post_sfdp hook since this capability is no longer set in Profile 1.0 parsing. - Instead of just checking for spi_nor_get_protocol_width() in spi_nor_octal_dtr_enable(), make sure the protocol is SNOR_PROTO_8_8_8_DTR since get_protocol_width() only cares about data width. - Drop flag SPI_NOR_SOFT_RESET. Instead, discover soft reset capability via BFPT. - Do not make an invalid Quad Enable BFPT field a fatal error. Silently ignore it by assuming no quad enable bit is present. - Set dummy cycles for Cypress Semper flash to 24 instead of 20. This allows for 200MHz operation in 8D mode compared to the 166MHz with 20. - Rename spi_nor_cypress_octal_enable() to spi_nor_cypress_octal_dtr_enable(). - Update spi-mtk-nor.c to reject DTR ops since it doesn't call spi_mem_default_supports_op(). Changes in v4: - Refactor the series to use the new spi-nor framework with the manufacturer-specific bits separated from the core. - Add support for Micron MT35XU512ABA. - Use cmd.nbytes as the criteria of whether the data phase exists or not instead of cmd.buf.in || cmd.buf.out in spi_nor_spimem_setup_op(). - Update Read FSR to use the same dummy cycles and address width as Read SR. - Fix BFPT parsing stopping too early for JESD216 rev B flashes. - Use 2 byte reads for Read SR and FSR commands in DTR mode. Changes in v3: - Drop the DT properties "spi-rx-dtr" and "spi-tx-dtr". Instead, if later a need is felt to disable DTR in case someone has a board with Octal DTR capable flash but does not support DTR transactions for some reason, a property like "spi-no-dtr" can be added. - Remove mode bits SPI_RX_DTR and SPI_TX_DTR. - Remove the Cadence Quadspi controller patch to un-block this series. I will submit it as a separate patch. - Rebase on latest 'master' and fix merge conflicts. - Update read and write dirmap templates to use DTR. - Rename 'is_dtr' to 'dtr'. - Make 'dtr' a bitfield. - Reject DTR ops in spi_mem_default_supports_op(). - Update atmel-quadspi to reject DTR ops. All other controller drivers call spi_mem_default_supports_op() so they will automatically reject DTR ops. - Add support for both enabling and disabling DTR modes. - Perform a Software Reset on flashes that support it when shutting down. - Disable Octal DTR mode on suspend, and re-enable it on resume. - Drop enum 'spi_mem_cmd_ext' and make command opcode u16 instead. Update spi-nor to use the 2-byte command instead of the command extension. Since we still need a "extension type", mode that enum to spi-nor and name it 'spi_nor_cmd_ext'. - Default variable address width to 3 to fix SMPT parsing. - Drop non-volatile change to uniform sector mode and rely on parsing SMPT. Changes in v2: - Add DT properties "spi-rx-dtr" and "spi-tx-dtr" to allow expressing DTR capabilities. - Set the mode bits SPI_RX_DTR and SPI_TX_DTR when we discover the DT properties "spi-rx-dtr" and spi-tx-dtr". - spi_nor_cypress_octal_enable() was updating nor->params.read[] with the intention of setting the correct number of dummy cycles. But this function is called _after_ selecting the read so setting nor->params.read[] will have no effect. So, update nor->read_dummy directly. - Fix spi_nor_spimem_check_readop() and spi_nor_spimem_check_pp() passing nor->read_proto and nor->write_proto to spi_nor_spimem_setup_op() instead of read->proto and pp->proto respectively. - Move the call to cqspi_setup_opcode_ext() inside cqspi_enable_dtr(). This avoids repeating the 'if (f_pdata->is_dtr) cqspi_setup_opcode_ext()...` snippet multiple times. - Call the default 'supports_op()' from cqspi_supports_mem_op(). This makes sure the buswidth requirements are also enforced along with the DTR requirements. - Drop the 'is_dtr' argument from spi_check_dtr_req(). We only call it when a phase is DTR so it is redundant. Pratyush Yadav (17): spi: spi-mem: allow specifying whether an op is DTR or not spi: spi-mem: allow specifying a command's extension spi: atmel-quadspi: reject DTR ops spi: spi-mtk-nor: reject DTR ops mtd: spi-nor: add support for DTR protocol mtd: spi-nor: sfdp: get command opcode extension type from BFPT mtd: spi-nor: sfdp: parse xSPI Profile 1.0 table mtd: spi-nor: core: use dummy cycle and address width info from SFDP mtd: spi-nor: core: do 2 byte reads for SR and FSR in DTR mode mtd: spi-nor: core: enable octal DTR mode when possible mtd: spi-nor: sfdp: do not make invalid quad enable fatal mtd: spi-nor: sfdp: detect Soft Reset sequence support from BFPT mtd: spi-nor: core: perform a Soft Reset on shutdown mtd: spi-nor: core: disable Octal DTR mode on suspend. mtd: spi-nor: core: expose spi_nor_default_setup() in core.h mtd: spi-nor: spansion: add support for Cypress Semper flash mtd: spi-nor: micron-st: allow using MT35XU512ABA in Octal DTR mode drivers/mtd/spi-nor/core.c | 446 +++++++++++++++++++++++++++----- drivers/mtd/spi-nor/core.h | 22 ++ drivers/mtd/spi-nor/micron-st.c | 103 +++++++- drivers/mtd/spi-nor/sfdp.c | 131 +++++++++- drivers/mtd/spi-nor/sfdp.h | 8 + drivers/mtd/spi-nor/spansion.c | 166 ++++++++++++ drivers/spi/atmel-quadspi.c | 6 + drivers/spi/spi-mem.c | 16 +- drivers/spi/spi-mtk-nor.c | 10 +- drivers/spi/spi-mxic.c | 3 +- drivers/spi/spi-zynq-qspi.c | 11 +- include/linux/mtd/spi-nor.h | 53 +++- include/linux/spi/spi-mem.h | 14 +- 13 files changed, 889 insertions(+), 100 deletions(-) -- 2.27.0 base-commit: b3a9e3b9 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
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Linus Walleij authored
The OMAP-100k driver includes <linux/gpio.h> but does not use any symbols from it, so drop the include. Signed-off-by:
Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20200714073357.34879-1-linus.walleij@linaro.orgSigned-off-by:
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Pratyush Yadav authored
Double Transfer Rate (DTR) ops are added in spi-mem. But this controller doesn't support DTR transactions. Since we don't use the default supports_op(), which rejects all DTR ops, do that explicitly in our supports_op(). Signed-off-by:
Pratyush Yadav <p.yadav@ti.com> Reviewed-by:
Tudor Ambarus <tudor.ambarus@microchip.com> Link: https://lore.kernel.org/r/20200623183030.26591-5-p.yadav@ti.comSigned-off-by:
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Pratyush Yadav authored
Double Transfer Rate (DTR) ops are added in spi-mem. But this controller doesn't support DTR transactions. Since we don't use the default supports_op(), which rejects all DTR ops, do that explicitly in our supports_op(). Signed-off-by:
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Pratyush Yadav authored
In xSPI mode, flashes expect 2-byte opcodes. The second byte is called the "command extension". There can be 3 types of extensions in xSPI: repeat, invert, and hex. When the extension type is "repeat", the same opcode is sent twice. When it is "invert", the second byte is the inverse of the opcode. When it is "hex" an additional opcode byte based is sent with the command whose value can be anything. So, make opcode a 16-bit value and add a 'nbytes', similar to how multiple address widths are handled. Some places use sizeof(op->cmd.opcode). Replace them with op->cmd.nbytes The spi-mxic and spi-zynq-qspi drivers directly use op->cmd.opcode as a buffer. Now that opcode is a 2-byte field, this can result in different behaviour depending on if the machine is little endian or big endian. Extract the opcode in a local 1-byte variable and use that as the buffer instead. Both these drivers would reject multi-byte opcodes in their supports_op() hook anyway, so we only need to worry about single-byte opcodes for now. The above two changes are put in this commit to keep the series bisectable. Signed-off-by:
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Pratyush Yadav authored
Each phase is given a separate 'dtr' field so mixed protocols like 4S-4D-4D can be supported. Signed-off-by:
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- 13 Jul, 2020 1 commit
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Linus Walleij authored
This converts the two Freescale i.MX SPI drivers Freescale i.MX (CONFIG_SPI_IMX) and Freescale i.MX LPSPI (CONFIG_SPI_FSL_LPSPI) to use GPIO descriptors handled in the SPI core for GPIO chip selects whether defined in the device tree or a board file. The reason why both are converted at the same time is that they were both using the same platform data and platform device population helpers when using board files intertwining the code so this gives a cleaner cut. The platform device creation was passing a platform data container from each boardfile down to the driver using struct spi_imx_master from <linux/platform_data/spi-imx.h>, but this was only conveying the number of chipselects and an int * array of the chipselect GPIO numbers. The imx27 and imx31 platforms had code passing the now-unused platform data when creating the platform devices, this has been repurposed to pass around GPIO descriptor tables. The platform data struct that was just passing an array of integers and number of chip selects for the GPIO lines has been removed. The number of chipselects used to be passed from the board file, because this number also limits the number of native chipselects that the platform can use. To deal with this we just augment the i.MX (CONFIG_SPI_IMX) driver to support 3 chipselects if the platform does not define "num-cs" as a device property (such as from the device tree). This covers all the legacy boards as these use <= 3 native chip selects (or GPIO lines, and in that case the number of chip selects is determined by the core from the number of available GPIO lines). Any new boards should use device tree, so this is a reasonable simplification to cover all old boards. The LPSPI driver never assigned the number of chipselects and thus always fall back to the core default of 1 chip select if no GPIOs are defined in the device tree. The Freescale i.MX driver was already partly utilizing the SPI core to obtain the GPIO numbers from the device tree, so this completes the transtion to let the core handle all of it. All board files and the core i.MX boardfile registration code is augmented to account for these changes. This has been compile-tested with the imx_v4_v5_defconfig and the imx_v6_v7_defconfig. Signed-off-by:
Shawn Guo <shawnguo@kernel.org> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: Robin Gong <yibin.gong@nxp.com> Cc: Trent Piepho <tpiepho@impinj.com> Cc: Clark Wang <xiaoning.wang@nxp.com> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Pengutronix Kernel Team <kernel@pengutronix.de> Cc: Fabio Estevam <festevam@gmail.com> Cc: NXP Linux Team <linux-imx@nxp.com> Link: https://lore.kernel.org/r/20200625200252.207614-1-linus.walleij@linaro.orgSigned-off-by:
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- 10 Jul, 2020 3 commits
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Anson Huang authored
Convert the i.MX LPSPI binding to DT schema format using json-schema Signed-off-by:
Anson Huang <Anson.Huang@nxp.com> Reviewed-by:
Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/1592281575-32708-4-git-send-email-Anson.Huang@nxp.comSigned-off-by:
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Anson Huang authored
Convert the i.MX CSPI binding to DT schema format using json-schema, update compatible, remove obsolete properties "fsl,spi-num-chipselects" and update the example based on latest DT file. Signed-off-by:
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Anson Huang authored
Convert the MXS SPI binding to DT schema format using json-schema Signed-off-by:
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- 09 Jul, 2020 3 commits
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Alexander A. Klimov authored
Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by:Alexander A. Klimov <grandmaster@al2klimov.de> Link: https://lore.kernel.org/r/20200708194400.22213-1-grandmaster@al2klimov.deSigned-off-by:
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Colin Ian King authored
The error exit label out_free is no longer being used, it is redundant and can be removed. Cleans up warning: drivers/spi/spi-atmel.c:1680:1: warning: label ‘out_free’ defined but not used [-Wunused-label] Fixes: 2d9a7446 ("spi: atmel: No need to call spi_master_put() if spi_alloc_master() failed") Signed-off-by:
Colin Ian King <colin.king@canonical.com> Link: https://lore.kernel.org/r/20200709101203.1374117-1-colin.king@canonical.comSigned-off-by:
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Marek Szyprowski authored
Use kthread_create_worker() helper to simplify the code. It uses the kthread worker API the right way. It will eventually allow to remove the FIXME in kthread_worker_fn() and add more consistency checks in the future. Signed-off-by:
Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by:
Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20200709065007.26896-1-m.szyprowski@samsung.comSigned-off-by:
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- 07 Jul, 2020 13 commits
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Mark Brown authored
Merge series "spi: spi-geni-qcom: Avoid a bunch of per-transfer overhead" from Douglas Anderson <dianders@chromium.org>: This series tries to reduce a whole bunch of overhead in each SPI transfer. Much of this overhead is new with the recent interconnect changes, but even without those changes we still had some overhead that we could avoid. Let's avoid all of it. These changes are atop the Qualcomm tree to avoid merge conflicts. If they look good, the most expedient way to land them is probably to get Ack's from Mark and land then via the Qualcomm tree. Most testing was done on the Chrome OS 5.4 tree, but sanity check was done on mainline. Douglas Anderson (3): spi: spi-geni-qcom: Avoid clock setting if not needed spi: spi-geni-qcom: Set an autosuspend delay of 250 ms spi: spi-geni-qcom: Get rid of most overhead in prepare_message() drivers/spi/spi-geni-qcom.c | 67 ++++++++++++++++++------------------- 1 file changed, 32 insertions(+), 35 deletions(-) -- 2.27.0.383.g050319c2ae-goog
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Mark Brown authored
Merge series "spi: spi-sun6i: One fix and some improvements" from Marc Kleine-Budde <mkl@pengutronix.de>: Hello, this series first fixes the calculation of the clock rate. The driver will round up to the nearest clock rate instead of rounding down. Resulting in SPI devices accessed with a too high SPI clock. The remaining patches improve the performance of the driver. The changes range from micro-optimizations like reducing MMIO writes to the controller to reducing the number of needed interrupts in some use cases. regards, Marc changes since v1: - added Maxime Ripard's to the existing patches - 06/10: (was 05/10 in v1) "spi: spi-sun6i: sun6i_spi_drain_fifo(): introduce sun6i_spi_get_rx_fifo_count() and make use of it" use FIELD_GET instead of open coding it (tnx: Maxime Ripard) - 05/10: "spi: spi-sun6i: sun6i_spi_get_tx_fifo_count: Convert manual shift+mask to FIELD_GET()" new patch _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
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Peng Fan authored
There is no need to call spi_master_put() if spi_alloc_master() failed, it should return -ENOMEM directly. Signed-off-by:
Peng Fan <fanpeng@loongson.cn> Link: https://lore.kernel.org/r/1594111842-9468-1-git-send-email-fanpeng@loongson.cnSigned-off-by:
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Douglas Anderson authored
In commit 0e3b8a81 ("spi: spi-geni-qcom: Add interconnect support") the spi_geni_runtime_suspend() and spi_geni_runtime_resume() became a bit slower. Measuring on my hardware I see numbers in the hundreds of microseconds now. Let's use autosuspend to help avoid some of the overhead. Now if we're doing a bunch of transfers we won't need to be constantly chruning. The number 250 ms for the autosuspend delay was picked a bit arbitrarily, so if someone has measurements showing a better value we could easily change this. Fixes: 0e3b8a81 ("spi: spi-geni-qcom: Add interconnect support") Signed-off-by:
Douglas Anderson <dianders@chromium.org> Reviewed-by: Akash Asthana<akashast@codeaurora.org> Link: https://lore.kernel.org/r/20200701174506.2.I9b8f6bb1e7e6d8847e2ed2cf854ec55678db427f@changeidSigned-off-by:
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Marc Kleine-Budde authored
In sun6i_spi_transfer_one() the RX FIFO Ready (SUN6I_INT_CTL_RF_RDY) is unconditionally enabled. A RX interrupt is only needed, if more data than fits into the FIFO is going to be received during this transfer. As the RX-FIFO is drained during transfer complete interrupt, enable the RX FIFO Ready interrupt only if the data doesn't fit into the FIFO. Signed-off-by:
Maxime Ripard <mripard@kernel.org> Link: https://lore.kernel.org/r/20200706143443.9855-11-mkl@pengutronix.deSigned-off-by:
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Marc Kleine-Budde authored
In sun6i_spi_transfer_one() the Interrupt Control Register is written three times. This patch collates the three writes into one. Signed-off-by:
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Marc Kleine-Budde authored
The function sun6i_spi_fill_fifo() is called with a length argument of "sspi->fifo_depth" and "SUN6I_FIFO_DEPTH". The driver reads the number of free bytes in the FIFO from the hardware and uses the length argument to limit this value. This is not needed as the number of free bytes in the FIFO is always less or equal the depth of the FIFO. This patch removes the length argument and check. Signed-off-by:
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Marc Kleine-Budde authored
The function sun6i_spi_drain_fifo() is called with a length argument of "sspi->fifo_depth" and "SUN6I_FIFO_DEPTH". The driver reads the number of available bytes to read from the FIFO from the hardware and uses the length argument to limit this value. This is not needed as the FIFO can contain only the fifo depth number of bytes. This patch removes the length argument and check. Signed-off-by:
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Marc Kleine-Budde authored
This patch introduces the function sun6i_spi_get_rx_fifo_count(), similar to the existing sun6i_spi_get_tx_fifo_count(), to make the sun6i_spi_drain_fifo() function a bit easier to read. Signed-off-by:
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Marc Kleine-Budde authored
This patch converts the manual shift+mask in sun6i_spi_get_tx_fifo_count() to make use of FIELD_GET() Signed-off-by:
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Marc Kleine-Budde authored
In sun6i_spi_transfer_one() the driver ensures that the length of the transfer is smaller or equal to SUN6I_MAX_XFER_SIZE. This means the masking of the length to SUN6I_MAX_XFER_SIZE can be skipped when writing the transfer length into the registers. This patch removes the useless masking of the transfer length to SUN6I_MAX_XFER_SIZE. Signed-off-by:
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Marc Kleine-Budde authored
This patch removes an useless goto at the end of sun6i_spi_transfer_one(). Signed-off-by:
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Marc Kleine-Budde authored
This patch implementes the reporting of the effectivly used speed_hz for the transfer by setting tfr->effective_speed_hz. See the following patch, which adds this feature to the SPI core for more information: 5d7e2b5e spi: core: allow reporting the effectivly used speed_hz for a transfer Signed-off-by:
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- 06 Jul, 2020 1 commit
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Marc Kleine-Budde authored
A SPI transfer defines the _maximum_ speed of the SPI transfer. However the driver doesn't take into account that the clock divider is always rounded down (due to integer arithmetics). This results in a too high clock rate for the SPI transfer. E.g.: with a mclk_rate of 24 MHz and a SPI transfer speed of 10 MHz, the original code calculates a reg of "0", which results in a effective divider of "2" and a 12 MHz clock for the SPI transfer. This patch fixes the issue by using DIV_ROUND_UP() instead of a plain integer division. While there simplify the divider calculation for the CDR1 case, use order_base_2() instead of two ilog2() calculations. Fixes: 3558fe90 ("spi: sunxi: Add Allwinner A31 SPI controller driver") Signed-off-by:
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- 01 Jul, 2020 11 commits
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Mark Brown authored
Merge series "Add Renesas RPC-IF support" from Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>: Hello! Here's a set of 2 patches against Linus' repo. Renesas Reduced Pin Count Interface (RPC-IF) allows a SPI flash or HyperFlash connected to the SoC to be accessed via the external address space read mode or the manual mode. The memory controller driver for RPC-IF registers either SPI or HyperFLash subdevice, depending on the contents of the device tree subnode; it also provides the abstract "back end" API that can be used by the "front end" SPI/MTD drivers to talk to the real hardware... Based on the original patch by Mason Yang <masonccyang@mxic.com.tw>. [1/2] dt-bindings: memory: document Renesas RPC-IF bindings [2/2] memory: add Renesas RPC-IF driver MBR, Sergei
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Mark Brown authored
Merge series "spi: bcm2835: Interrupt-handling optimisations" from Robin Murphy <robin.murphy@arm.com>: Hi all, Although Florian was concerned about a trivial inline check to deal with shared IRQs adding overhead, the reality is that it would be so small as to not be worth even thinking about unless the driver was already tuned to squeeze out every last cycle. And a brief look over the code shows that that clearly isn't the case. This is an example of some of the easy low-hanging fruit that jumps out just from code inspection. Based on disassembly and ARM1176 cycle timings, patch #2 should save the equivalent of 2-3 shared interrupt checks off the critical path in all cases, and patch #3 possibly up to about 100x more. I don't have any means to test these patches, let alone measure performance, so they're only backed by the principle that less code - and in particular fewer memory accesses - is almost always better. There is almost certainly a *lot* more to be had from careful use of relaxed I/O accessors, not doing a read-modify-write of CS at every reset, tweaking the loops further to avoid unnecessary writebacks to variables, and so on. However since I'm not invested in this personally I'm not going to pursue it any further; I'm throwing these patches out as more of a demonstration to back up my original drive-by review comments, so if anyone want to pick them up and run with them then please do so. Robin. Robin Murphy (3): spi: bcm3835: Tidy up bcm2835_spi_reset_hw() spi: bcm2835: Micro-optimise IRQ handler spi: bcm2835: Micro-optimise FIFO loops drivers/spi/spi-bcm2835.c | 45 +++++++++++++++++++-------------------- 1 file changed, 22 insertions(+), 23 deletions(-) -- 2.23.0.dirty _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
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Linus Walleij authored
This switches the Lantiq SSC driver over to use GPIO descriptor handling in the core. The driver was already utilizing the core to look up and request GPIOs from the device tree so this is a pretty small change just switching it over to use descriptors directly instead. Signed-off-by:
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Linus Walleij authored
This converts the IMG SPFI SPI driver to use GPIO descriptors as obtained from the core instead of GPIO numbers. The driver was already relying on the core code to look up the GPIO numbers from the device tree and allocate memory for storing state etc. By moving to use descriptors handled by the core we can delete the setup/cleanup functions and the device state handler that were only dealing with this. Signed-off-by:
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Linus Walleij authored
The Nuvoton PSPI driver already uses the core to handle GPIO chip selects but is using the old GPIO number method and retrieveing the GPIOs in the probe() call. Switch it over to using GPIO descriptors saving a bunch of code and modernizing it. Compile tested med ARMv7 multiplatform config augmented with the Nuvoton arch and this driver. Signed-off-by:
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Douglas Anderson authored
On some SPI controllers (like spi-geni-qcom) setting the chip select is a heavy operation. For instance on spi-geni-qcom, with the current code, is was measured as taking upwards of 20 us. Even on SPI controllers that aren't as heavy, setting the chip select is at least something like a MMIO operation over some peripheral bus which isn't as fast as a RAM access. While it would be good to find ways to mitigate problems like this in the drivers for those SPI controllers, it can also be noted that the SPI framework could also help out. Specifically, in some situations, we can see the SPI framework calling the driver's set_cs() with the same parameter several times in a row. This is specifically observed when looking at the way the Chrome OS EC SPI driver (cros_ec_spi) works but other drivers likely trip it to some extent. Let's solve this by caching the chip select state in the core and only calling into the controller if there was a change. We check not only the "enable" state but also the chip select mode (active high or active low) since controllers may care about both the mode and the enable flag in their callback. Signed-off-by:
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Luc Van Oostenryck authored
The field mspi->reg_base is annotated as an __iomem pointer. Good. However, this field is often assigned to a temporary variable: before being used. For example: struct fsl_spi_reg *reg_base = mspi->reg_base; But this variable is missing the __iomem annotation. So, add the missing __iomem and make sparse & the bot happier. Reported-by:
kernel test robot <lkp@intel.com> Signed-off-by:
Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Link: https://lore.kernel.org/r/20200622162611.83694-1-luc.vanoostenryck@gmail.comSigned-off-by:
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Sergei Shtylyov authored
Add the memory driver for Renesas RPC-IF which registers either SPI or HyperFLash device depending on the contents of the device tree subnode. It also provides the absract "back end" device APIs that can be used by the "front end" SPI/MTD drivers to talk to the real hardware. Based on the original patch by Mason Yang <masonccyang@mxic.com.tw>. Signed-off-by:
Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Link: https://lore.kernel.org/r/9a3606ec-d4d0-c63a-4fb6-631ab38e621c@cogentembedded.comSigned-off-by:
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Sergei Shtylyov authored
Renesas Reduced Pin Count Interface (RPC-IF) allows a SPI flash or HyperFlash connected to the SoC to be accessed via the external address space read mode or the manual mode. Document the device tree bindings for the Renesas RPC-IF found in the R-Car gen3 SoCs. Based on the original patch by Mason Yang <masonccyang@mxic.com.tw>. Signed-off-by:
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Robin Murphy authored
The blind and counted loops are always called with nonzero count, so convert them to do-while loops that lead to slightly more efficient code generation. With GCC 8.3 this shaves off 1-2 instructions per iteration in each case. Signed-off-by:
Robin Murphy <robin.murphy@arm.com> Link: https://lore.kernel.org/r/9242863077acf9a64e4b3720e479855b88d19e82.1592261248.git.robin.murphy@arm.comSigned-off-by:
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Robin Murphy authored
The IRQ handler only needs the struct spi_controller for the sake of the completion at the end of a transfer. Passing the struct bcm2835_spi directly as the IRQ data allows that level of indirection to be pushed into the completion path for the reverse lookup, and avoided entirely in all other cases. This saves one explicit load in the critical path, plus (for a GCC 8.3 build) two registers worth of stack frame overhead. Signed-off-by:
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