On 29.06.2018 13:33, Krzysztof Kozlowski wrote: > Registers of DSPI should not be accessed before enabling its clock. On > Toradex Colibri VF50 on Iris carrier board this could be seen during > bootup as imprecise abort: > > Unhandled fault: imprecise external abort (0x1c06) at 0x00000000 > Internal error: : 1c06 [#1] ARM > Modules linked in: > CPU: 0 PID: 1 Comm: swapper Not tainted 4.14.39-dirty #97 > Hardware name: Freescale Vybrid VF5xx/VF6xx (Device Tree) > Backtrace: > [<804166a8>] (regmap_write) from [<80466b5c>] (dspi_probe+0x1f0/0x8dc) > [<8046696c>] (dspi_probe) from [<8040107c>] (platform_drv_probe+0x54/0xb8) > [<80401028>] (platform_drv_probe) from [<803ff53c>] > (driver_probe_device+0x280/0x2f8) > [<803ff2bc>] (driver_probe_device) from [<803ff674>] > (__driver_attach+0xc0/0xc4) > [<803ff5b4>] (__driver_attach) from [<803fd818>] > (bus_for_each_dev+0x70/0xa4) > [<803fd7a8>] (bus_for_each_dev) from [<803fee74>] > (driver_attach+0x24/0x28) > [<803fee50>] (driver_attach) from [<803fe980>] > (bus_add_driver+0x1a0/0x218) > [<803fe7e0>] (bus_add_driver) from [<803fffe8>] > (driver_register+0x80/0x100) > [<803fff68>] (driver_register) from [<80400fdc>] > (__platform_driver_register+0x48/0x50) > [<80400f94>] (__platform_driver_register) from [<8091cf7c>] > (fsl_dspi_driver_init+0x1c/0x20) > [<8091cf60>] (fsl_dspi_driver_init) from [<8010195c>] > (do_one_initcall+0x4c/0x174) > [<80101910>] (do_one_initcall) from [<80900e8c>] > (kernel_init_freeable+0x144/0x1d8) > [<80900d48>] (kernel_init_freeable) from [<805ff6a8>] > (kernel_init+0x10/0x114) > [<805ff698>] (kernel_init) from [<80107be8>] (ret_from_fork+0x14/0x2c) > > Cc: <[email protected]> > Fixes: 5ee67b587a2b ("spi: dspi: clear SPI_SR before enable interrupt") > Signed-off-by: Krzysztof Kozlowski <[email protected]>
Reviewed-by: Stefan Agner <[email protected]> Up until commit d2233325e5b7 ("spi: spi-fsl-dspi: remove clk reference when regmap_mmio initialize") regmap with clocks has been used. I guess an alternative would have been to use this again, but I guess this has been dropped for good reasons. -- Stefan > --- > drivers/spi/spi-fsl-dspi.c | 24 ++++++++++++------------ > 1 file changed, 12 insertions(+), 12 deletions(-) > > diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c > index ff7456be9d6d..89a1e7a4fe5d 100644 > --- a/drivers/spi/spi-fsl-dspi.c > +++ b/drivers/spi/spi-fsl-dspi.c > @@ -1071,30 +1071,30 @@ static int dspi_probe(struct platform_device *pdev) > } > } > > + dspi->clk = devm_clk_get(&pdev->dev, "dspi"); > + if (IS_ERR(dspi->clk)) { > + ret = PTR_ERR(dspi->clk); > + dev_err(&pdev->dev, "unable to get clock\n"); > + goto out_master_put; > + } > + ret = clk_prepare_enable(dspi->clk); > + if (ret) > + goto out_master_put; > + > dspi_init(dspi); > dspi->irq = platform_get_irq(pdev, 0); > if (dspi->irq < 0) { > dev_err(&pdev->dev, "can't get platform irq\n"); > ret = dspi->irq; > - goto out_master_put; > + goto out_clk_put; > } > > ret = devm_request_irq(&pdev->dev, dspi->irq, dspi_interrupt, 0, > pdev->name, dspi); > if (ret < 0) { > dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n"); > - goto out_master_put; > - } > - > - dspi->clk = devm_clk_get(&pdev->dev, "dspi"); > - if (IS_ERR(dspi->clk)) { > - ret = PTR_ERR(dspi->clk); > - dev_err(&pdev->dev, "unable to get clock\n"); > - goto out_master_put; > + goto out_clk_put; > } > - ret = clk_prepare_enable(dspi->clk); > - if (ret) > - goto out_master_put; > > if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) { > ret = dspi_request_dma(dspi, res->start);
