* [PATCH AUTOSEL 5.1 007/219] spi: rockchip: turn down tx dma bursts [not found] <20190715140341.6443-1-sashal@kernel.org> @ 2019-07-15 14:00 ` Sasha Levin 2019-07-15 14:01 ` [PATCH AUTOSEL 5.1 115/219] spi: fix ctrl->num_chipselect constraint Sasha Levin 1 sibling, 0 replies; 3+ messages in thread From: Sasha Levin @ 2019-07-15 14:00 UTC (permalink / raw) To: linux-kernel, stable Cc: Emil Renner Berthing, Mark Brown, Sasha Levin, linux-spi, linux-rockchip From: Emil Renner Berthing <kernel@esmil.dk> [ Upstream commit 47300728fb213486a830565d2af49da967c9d16a ] This fixes tx and bi-directional dma transfers on rk3399-gru-kevin. It seems the SPI fifo must have room for 2 bursts when the dma_tx_req signal is generated or it might skip some words. This in turn makes the rx dma channel never complete for bi-directional transfers. Fix it by setting tx burst length to fifo_len / 4 and the dma watermark to fifo_len / 2. However the rk3399 TRM says (sic): "DMAC support incrementing-address burst and fixed-address burst. But in the case of access SPI and UART at byte or halfword size, DMAC only support fixed-address burst and the address must be aligned to word." So this relies on fifo_len being a multiple of 16 such that the burst length (= fifo_len / 4) is a multiple of 4 and the addresses will be word-aligned. Fixes: dcfc861d24ec ("spi: rockchip: adjust dma watermark and burstlen") Signed-off-by: Emil Renner Berthing <kernel@esmil.dk> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/spi/spi-rockchip.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index 3912526ead66..19f6a76f1c07 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -425,7 +425,7 @@ static int rockchip_spi_prepare_dma(struct rockchip_spi *rs, .direction = DMA_MEM_TO_DEV, .dst_addr = rs->dma_addr_tx, .dst_addr_width = rs->n_bytes, - .dst_maxburst = rs->fifo_len / 2, + .dst_maxburst = rs->fifo_len / 4, }; dmaengine_slave_config(master->dma_tx, &txconf); @@ -526,7 +526,7 @@ static void rockchip_spi_config(struct rockchip_spi *rs, else writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR); - writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_DMATDLR); + writel_relaxed(rs->fifo_len / 2, rs->regs + ROCKCHIP_SPI_DMATDLR); writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMARDLR); writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR); -- 2.20.1 ^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH AUTOSEL 5.1 115/219] spi: fix ctrl->num_chipselect constraint [not found] <20190715140341.6443-1-sashal@kernel.org> 2019-07-15 14:00 ` [PATCH AUTOSEL 5.1 007/219] spi: rockchip: turn down tx dma bursts Sasha Levin @ 2019-07-15 14:01 ` Sasha Levin 1 sibling, 0 replies; 3+ messages in thread From: Sasha Levin @ 2019-07-15 14:01 UTC (permalink / raw) To: linux-kernel, stable; +Cc: Tudor Ambarus, Mark Brown, Sasha Levin, linux-spi From: Tudor Ambarus <tudor.ambarus@microchip.com> [ Upstream commit f9481b08220d7dc1ff21e296a330ee8b721b44e4 ] at91sam9g25ek showed the following error at probe: atmel_spi f0000000.spi: Using dma0chan2 (tx) and dma0chan3 (rx) for DMA transfers atmel_spi: probe of f0000000.spi failed with error -22 Commit 0a919ae49223 ("spi: Don't call spi_get_gpio_descs() before device name is set") moved the calling of spi_get_gpio_descs() after ctrl->dev is set, but didn't move the !ctrl->num_chipselect check. When there are chip selects in the device tree, the spi-atmel driver lets the SPI core discover them when registering the SPI master. The ctrl->num_chipselect is thus expected to be set by spi_get_gpio_descs(). Move the !ctlr->num_chipselect after spi_get_gpio_descs() as it was before the aforementioned commit. While touching this block, get rid of the explicit comparison with 0 and update the commenting style. Fixes: 0a919ae49223 ("spi: Don't call spi_get_gpio_descs() before device name is set") Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/spi/spi.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index a83fcddf1dad..7f6fb383d7a7 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2281,11 +2281,6 @@ int spi_register_controller(struct spi_controller *ctlr) if (status) return status; - /* even if it's just one always-selected device, there must - * be at least one chipselect - */ - if (ctlr->num_chipselect == 0) - return -EINVAL; if (ctlr->bus_num >= 0) { /* devices with a fixed bus num must check-in with the num */ mutex_lock(&board_lock); @@ -2356,6 +2351,13 @@ int spi_register_controller(struct spi_controller *ctlr) } } + /* + * Even if it's just one always-selected device, there must + * be at least one chipselect. + */ + if (!ctlr->num_chipselect) + return -EINVAL; + status = device_add(&ctlr->dev); if (status < 0) { /* free bus id */ -- 2.20.1 ^ permalink raw reply related [flat|nested] 3+ messages in thread
[parent not found: <20190715133811.2441-1-sashal@kernel.org>]
* [PATCH AUTOSEL 5.1 007/219] spi: rockchip: turn down tx dma bursts [not found] <20190715133811.2441-1-sashal@kernel.org> @ 2019-07-15 13:34 ` Sasha Levin 0 siblings, 0 replies; 3+ messages in thread From: Sasha Levin @ 2019-07-15 13:34 UTC (permalink / raw) To: linux-kernel, stable Cc: Emil Renner Berthing, Mark Brown, Sasha Levin, linux-spi, linux-rockchip From: Emil Renner Berthing <kernel@esmil.dk> [ Upstream commit 47300728fb213486a830565d2af49da967c9d16a ] This fixes tx and bi-directional dma transfers on rk3399-gru-kevin. It seems the SPI fifo must have room for 2 bursts when the dma_tx_req signal is generated or it might skip some words. This in turn makes the rx dma channel never complete for bi-directional transfers. Fix it by setting tx burst length to fifo_len / 4 and the dma watermark to fifo_len / 2. However the rk3399 TRM says (sic): "DMAC support incrementing-address burst and fixed-address burst. But in the case of access SPI and UART at byte or halfword size, DMAC only support fixed-address burst and the address must be aligned to word." So this relies on fifo_len being a multiple of 16 such that the burst length (= fifo_len / 4) is a multiple of 4 and the addresses will be word-aligned. Fixes: dcfc861d24ec ("spi: rockchip: adjust dma watermark and burstlen") Signed-off-by: Emil Renner Berthing <kernel@esmil.dk> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/spi/spi-rockchip.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index 3912526ead66..19f6a76f1c07 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -425,7 +425,7 @@ static int rockchip_spi_prepare_dma(struct rockchip_spi *rs, .direction = DMA_MEM_TO_DEV, .dst_addr = rs->dma_addr_tx, .dst_addr_width = rs->n_bytes, - .dst_maxburst = rs->fifo_len / 2, + .dst_maxburst = rs->fifo_len / 4, }; dmaengine_slave_config(master->dma_tx, &txconf); @@ -526,7 +526,7 @@ static void rockchip_spi_config(struct rockchip_spi *rs, else writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR); - writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_DMATDLR); + writel_relaxed(rs->fifo_len / 2, rs->regs + ROCKCHIP_SPI_DMATDLR); writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMARDLR); writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR); -- 2.20.1 ^ permalink raw reply related [flat|nested] 3+ messages in thread
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[not found] <20190715140341.6443-1-sashal@kernel.org>
2019-07-15 14:00 ` [PATCH AUTOSEL 5.1 007/219] spi: rockchip: turn down tx dma bursts Sasha Levin
2019-07-15 14:01 ` [PATCH AUTOSEL 5.1 115/219] spi: fix ctrl->num_chipselect constraint Sasha Levin
[not found] <20190715133811.2441-1-sashal@kernel.org>
2019-07-15 13:34 ` [PATCH AUTOSEL 5.1 007/219] spi: rockchip: turn down tx dma bursts Sasha Levin
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