From e6419c35f0d92632e06708c5610a31957f1bd6b3 Mon Sep 17 00:00:00 2001 From: Stephan Gerhold Date: Tue, 19 Sep 2023 13:59:48 +0200 Subject: spi: dt-bindings: qup: Document power-domains and OPP Document power-domains and operating-points-v2 to allow making performance state votes for certain clock frequencies of the SPI QUP controller. Reviewed-by: Krzysztof Kozlowski Signed-off-by: Stephan Gerhold Link: https://lore.kernel.org/r/20230919-spi-qup-dvfs-v2-1-1bac2e9ab8db@kernkonzept.com Signed-off-by: Mark Brown --- Documentation/devicetree/bindings/spi/qcom,spi-qup.yaml | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/Documentation/devicetree/bindings/spi/qcom,spi-qup.yaml b/Documentation/devicetree/bindings/spi/qcom,spi-qup.yaml index 93f14dd01afc..1e498a791406 100644 --- a/Documentation/devicetree/bindings/spi/qcom,spi-qup.yaml +++ b/Documentation/devicetree/bindings/spi/qcom,spi-qup.yaml @@ -47,6 +47,11 @@ properties: interrupts: maxItems: 1 + operating-points-v2: true + + power-domains: + maxItems: 1 + reg: maxItems: 1 @@ -63,6 +68,7 @@ examples: - | #include #include + #include spi@7575000 { compatible = "qcom,spi-qup-v2.2.1"; @@ -76,6 +82,8 @@ examples: pinctrl-1 = <&blsp1_spi1_sleep>; dmas = <&blsp1_dma 12>, <&blsp1_dma 13>; dma-names = "tx", "rx"; + power-domains = <&rpmpd MSM8996_VDDCX>; + operating-points-v2 = <&spi_opp_table>; #address-cells = <1>; #size-cells = <0>; }; -- cgit From 287fcdaa35fc666640f805310095c52f2d818d26 Mon Sep 17 00:00:00 2001 From: Stephan Gerhold Date: Tue, 19 Sep 2023 13:59:49 +0200 Subject: spi: qup: Parse OPP table for DVFS support Parse the OPP table from the device tree and use dev_pm_opp_set_rate() instead of clk_set_rate() to allow making performance state for power domains specified in the OPP table. This is needed to guarantee correct behavior of the clock, especially with the higher clock/SPI bus frequencies. Acked-by: Konrad Dybcio Signed-off-by: Stephan Gerhold Link: https://lore.kernel.org/r/20230919-spi-qup-dvfs-v2-2-1bac2e9ab8db@kernkonzept.com Signed-off-by: Mark Brown --- drivers/spi/spi-qup.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c index 4b6f6b25219b..bf043be3a2a9 100644 --- a/drivers/spi/spi-qup.c +++ b/drivers/spi/spi-qup.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -667,7 +668,7 @@ static int spi_qup_io_prep(struct spi_device *spi, struct spi_transfer *xfer) return -EIO; } - ret = clk_set_rate(controller->cclk, xfer->speed_hz); + ret = dev_pm_opp_set_rate(controller->dev, xfer->speed_hz); if (ret) { dev_err(controller->dev, "fail to set frequency %d", xfer->speed_hz); @@ -1027,6 +1028,15 @@ static int spi_qup_probe(struct platform_device *pdev) return -ENXIO; } + ret = devm_pm_opp_set_clkname(dev, "core"); + if (ret) + return ret; + + /* OPP table is optional */ + ret = devm_pm_opp_of_add_table(dev); + if (ret && ret != -ENODEV) + return dev_err_probe(dev, ret, "invalid OPP table\n"); + host = spi_alloc_host(dev, sizeof(struct spi_qup)); if (!host) { dev_err(dev, "cannot allocate host\n"); -- cgit From d15befc0cef42db7712714157d9483cab81149a1 Mon Sep 17 00:00:00 2001 From: Stephan Gerhold Date: Tue, 19 Sep 2023 13:59:50 +0200 Subject: spi: dt-bindings: qup: Document interconnects When the SPI QUP controller is used together with a DMA engine it needs to vote for the interconnect path to the DRAM. Otherwise it may be unable to access the memory quickly enough. Reviewed-by: Krzysztof Kozlowski Signed-off-by: Stephan Gerhold Link: https://lore.kernel.org/r/20230919-spi-qup-dvfs-v2-3-1bac2e9ab8db@kernkonzept.com Signed-off-by: Mark Brown --- Documentation/devicetree/bindings/spi/qcom,spi-qup.yaml | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/Documentation/devicetree/bindings/spi/qcom,spi-qup.yaml b/Documentation/devicetree/bindings/spi/qcom,spi-qup.yaml index 1e498a791406..88be13268962 100644 --- a/Documentation/devicetree/bindings/spi/qcom,spi-qup.yaml +++ b/Documentation/devicetree/bindings/spi/qcom,spi-qup.yaml @@ -44,6 +44,9 @@ properties: - const: tx - const: rx + interconnects: + maxItems: 1 + interrupts: maxItems: 1 @@ -67,6 +70,7 @@ unevaluatedProperties: false examples: - | #include + #include #include #include @@ -84,6 +88,7 @@ examples: dma-names = "tx", "rx"; power-domains = <&rpmpd MSM8996_VDDCX>; operating-points-v2 = <&spi_opp_table>; + interconnects = <&pnoc MASTER_BLSP_1 &bimc SLAVE_EBI_CH0>; #address-cells = <1>; #size-cells = <0>; }; -- cgit From ecdaa9473019f94e0ad6974a5f69b9be7de137d3 Mon Sep 17 00:00:00 2001 From: Stephan Gerhold Date: Tue, 19 Sep 2023 13:59:51 +0200 Subject: spi: qup: Vote for interconnect bandwidth to DRAM When the SPI QUP controller is used together with a DMA engine it needs to vote for the interconnect path to the DRAM. Otherwise it may be unable to access the memory quickly enough. The requested peak bandwidth is dependent on the SPI core/bus clock so that the bandwidth scales together with the selected SPI speed. To avoid sending votes too often the bandwidth is always requested when a DMA transfer starts, but dropped only on runtime suspend. Runtime suspend should only happen if no transfer is active. After resumption we can defer the next vote until the first DMA transfer actually happens. Signed-off-by: Stephan Gerhold Link: https://lore.kernel.org/r/20230919-spi-qup-dvfs-v2-4-1bac2e9ab8db@kernkonzept.com Signed-off-by: Mark Brown --- drivers/spi/spi-qup.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c index bf043be3a2a9..2af63040ac6e 100644 --- a/drivers/spi/spi-qup.c +++ b/drivers/spi/spi-qup.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include #include @@ -122,11 +123,14 @@ #define SPI_DELAY_THRESHOLD 1 #define SPI_DELAY_RETRY 10 +#define SPI_BUS_WIDTH 8 + struct spi_qup { void __iomem *base; struct device *dev; struct clk *cclk; /* core clock */ struct clk *iclk; /* interface clock */ + struct icc_path *icc_path; /* interconnect to RAM */ int irq; spinlock_t lock; @@ -149,6 +153,8 @@ struct spi_qup { int mode; struct dma_slave_config rx_conf; struct dma_slave_config tx_conf; + + u32 bw_speed_hz; }; static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer); @@ -181,6 +187,23 @@ static inline bool spi_qup_is_valid_state(struct spi_qup *controller) return opstate & QUP_STATE_VALID; } +static int spi_qup_vote_bw(struct spi_qup *controller, u32 speed_hz) +{ + u32 needed_peak_bw; + int ret; + + if (controller->bw_speed_hz == speed_hz) + return 0; + + needed_peak_bw = Bps_to_icc(speed_hz * SPI_BUS_WIDTH); + ret = icc_set_bw(controller->icc_path, 0, needed_peak_bw); + if (ret) + return ret; + + controller->bw_speed_hz = speed_hz; + return 0; +} + static int spi_qup_set_state(struct spi_qup *controller, u32 state) { unsigned long loop; @@ -451,6 +474,12 @@ static int spi_qup_do_dma(struct spi_device *spi, struct spi_transfer *xfer, struct scatterlist *tx_sgl, *rx_sgl; int ret; + ret = spi_qup_vote_bw(qup, xfer->speed_hz); + if (ret) { + dev_err(qup->dev, "fail to vote for ICC bandwidth: %d\n", ret); + return -EIO; + } + if (xfer->rx_buf) rx_done = spi_qup_dma_done; else if (xfer->tx_buf) @@ -994,6 +1023,7 @@ static void spi_qup_set_cs(struct spi_device *spi, bool val) static int spi_qup_probe(struct platform_device *pdev) { struct spi_controller *host; + struct icc_path *icc_path; struct clk *iclk, *cclk; struct spi_qup *controller; struct resource *res; @@ -1019,6 +1049,11 @@ static int spi_qup_probe(struct platform_device *pdev) if (IS_ERR(iclk)) return PTR_ERR(iclk); + icc_path = devm_of_icc_get(dev, NULL); + if (IS_ERR(icc_path)) + return dev_err_probe(dev, PTR_ERR(icc_path), + "failed to get interconnect path\n"); + /* This is optional parameter */ if (of_property_read_u32(dev->of_node, "spi-max-frequency", &max_freq)) max_freq = SPI_MAX_RATE; @@ -1070,6 +1105,7 @@ static int spi_qup_probe(struct platform_device *pdev) controller->base = base; controller->iclk = iclk; controller->cclk = cclk; + controller->icc_path = icc_path; controller->irq = irq; ret = spi_qup_init_dma(host, res->start); @@ -1190,6 +1226,7 @@ static int spi_qup_pm_suspend_runtime(struct device *device) writel_relaxed(config, controller->base + QUP_CONFIG); clk_disable_unprepare(controller->cclk); + spi_qup_vote_bw(controller, 0); clk_disable_unprepare(controller->iclk); return 0; @@ -1241,6 +1278,7 @@ static int spi_qup_suspend(struct device *device) return ret; clk_disable_unprepare(controller->cclk); + spi_qup_vote_bw(controller, 0); clk_disable_unprepare(controller->iclk); return 0; } -- cgit