From: Thomas Kopp <thomas.kopp@microchip.com>
To: <linux-can@vger.kernel.org>
Cc: <mkl@pengutronix.de>, <kernel@pengutronix.de>,
<dev.kurt@vandijck-laurijssen.be>,
<manivannan.sadhasivam@linaro.org>
Subject: [PATCH] can: mcp25xxfd: Limit spiclk to 0.85*(sysclk/2)
Date: Wed, 16 Sep 2020 12:08:23 +0200 [thread overview]
Message-ID: <20200916100823.1105-1-thomas.kopp@microchip.com> (raw)
Signed-off-by: Thomas Kopp <thomas.kopp@microchip.com>
---
drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c b/drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c
index 6ffa7af50119..670b7d1e1f46 100644
--- a/drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c
+++ b/drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c
@@ -2821,11 +2821,13 @@ static int mcp25xxfd_probe(struct spi_device *spi)
* 2518 40 MHz allwinner,sun8i-h3 allwinner,sun8i-h3-spi 18750000 Hz 93.75% 600000000 Hz bad assigned-clocks = <&ccu CLK_SPIx>
* 2517 20 MHz fsl,imx8mm fsl,imx51-ecspi 9090909 Hz 90.09% 18181819 Hz good assigned-clocks = <&clk IMX8MM_CLK_ECSPIx_ROOT>
* 2517 20 MHz fsl,imx8mm fsl,imx51-ecspi 9523809 Hz 95.34% 28571429 Hz bad assigned-clocks = <&clk IMX8MM_CLK_ECSPIx_ROOT>
+ * 2517 40 MHz atmel,sama5d27 atmel,at91rm9200-spi 16400000 Hz 82% 82000000 Hz good default
+ * 2518 40 MHz atmel,sama5d27 atmel,at91rm9200-spi 16400000 Hz 82% 82000000 Hz good default
*
- * Limit SPI clock to 92.5% of SYSCLOCK / 2 for now.
+ * Limit SPI clock to 85% of SYSCLOCK / 2 for now.
*/
priv->spi_max_speed_hz_orig = spi->max_speed_hz;
- spi->max_speed_hz = min(spi->max_speed_hz, freq / 2 / 1000 * 925);
+ spi->max_speed_hz = min(spi->max_speed_hz, freq / 2 / 1000 * 850);
spi->bits_per_word = 8;
spi->rt = true;
err = spi_setup(spi);
--
2.25.1
next reply other threads:[~2020-09-16 10:09 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-16 10:08 Thomas Kopp [this message]
2020-09-16 10:20 ` [PATCH] can: mcp25xxfd: Limit spiclk to 0.85*(sysclk/2) Marc Kleine-Budde
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