From 8fc13b822c74a46587c0d8aae4ea0820b6bdb933 Mon Sep 17 00:00:00 2001 From: David Lechner Date: Mon, 28 Apr 2025 15:58:57 -0500 Subject: [PATCH] spi: axi-spi-engine: don't repeat mode config for offload Add an optimization to avoid repeating the config instruction in each SPI message when using SPI offloading. Instead, the instruction is run once when the SPI offload trigger is enabled. This is done to allow higher sample rates for ADCs using this SPI controller. Signed-off-by: David Lechner Link: https://patch.msgid.link/20250428-adi-main-v1-2-4b8a1b88a212@baylibre.com Signed-off-by: Mark Brown --- drivers/spi/spi-axi-spi-engine.c | 33 +++++++++++++++++++++++++++++--- 1 file changed, 30 insertions(+), 3 deletions(-) diff --git a/drivers/spi/spi-axi-spi-engine.c b/drivers/spi/spi-axi-spi-engine.c index d040deffa9bb..05ef2589f8dc 100644 --- a/drivers/spi/spi-axi-spi-engine.c +++ b/drivers/spi/spi-axi-spi-engine.c @@ -141,6 +141,7 @@ struct spi_engine_offload { struct spi_engine *spi_engine; unsigned long flags; unsigned int offload_num; + unsigned int spi_mode_config; }; struct spi_engine { @@ -284,6 +285,7 @@ static void spi_engine_compile_message(struct spi_message *msg, bool dry, { struct spi_device *spi = msg->spi; struct spi_controller *host = spi->controller; + struct spi_engine_offload *priv; struct spi_transfer *xfer; int clk_div, new_clk_div, inst_ns; bool keep_cs = false; @@ -297,9 +299,18 @@ static void spi_engine_compile_message(struct spi_message *msg, bool dry, clk_div = 1; - spi_engine_program_add_cmd(p, dry, - SPI_ENGINE_CMD_WRITE(SPI_ENGINE_CMD_REG_CONFIG, - spi_engine_get_config(spi))); + /* + * As an optimization, SPI offload sets once this when the offload is + * enabled instead of repeating the instruction in each message. + */ + if (msg->offload) { + priv = msg->offload->priv; + priv->spi_mode_config = spi_engine_get_config(spi); + } else { + spi_engine_program_add_cmd(p, dry, + SPI_ENGINE_CMD_WRITE(SPI_ENGINE_CMD_REG_CONFIG, + spi_engine_get_config(spi))); + } xfer = list_first_entry(&msg->transfers, struct spi_transfer, transfer_list); spi_engine_gen_cs(p, dry, spi, !xfer->cs_off); @@ -842,6 +853,22 @@ static int spi_engine_trigger_enable(struct spi_offload *offload) struct spi_engine_offload *priv = offload->priv; struct spi_engine *spi_engine = priv->spi_engine; unsigned int reg; + int ret; + + writel_relaxed(SPI_ENGINE_CMD_SYNC(0), + spi_engine->base + SPI_ENGINE_REG_CMD_FIFO); + + writel_relaxed(SPI_ENGINE_CMD_WRITE(SPI_ENGINE_CMD_REG_CONFIG, + priv->spi_mode_config), + spi_engine->base + SPI_ENGINE_REG_CMD_FIFO); + + writel_relaxed(SPI_ENGINE_CMD_SYNC(1), + spi_engine->base + SPI_ENGINE_REG_CMD_FIFO); + + ret = readl_relaxed_poll_timeout(spi_engine->base + SPI_ENGINE_REG_SYNC_ID, + reg, reg == 1, 1, 1000); + if (ret) + return ret; reg = readl_relaxed(spi_engine->base + SPI_ENGINE_REG_OFFLOAD_CTRL(priv->offload_num)); -- 2.25.1