From 3a01f04d74ef7597104f3ace8a053761cb2ac349 Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Mon, 20 Apr 2020 15:08:47 -0400 Subject: [PATCH] spi: bcm-qspi: Handle lack of MSPI_REV offset Older MIPS chips have a QSPI/MSPI controller that does not have the MSPI_REV offset, reading from that offset will cause a bus error. Match their compatible string and do not perform a read from that register in that case. Signed-off-by: Florian Fainelli Signed-off-by: Kamal Dasu Link: https://lore.kernel.org/r/20200420190853.45614-4-kdasu.kdev@gmail.com Signed-off-by: Mark Brown --- drivers/spi/spi-bcm-qspi.c | 50 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 48 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c index 23d295f..1f157c3 100644 --- a/drivers/spi/spi-bcm-qspi.c +++ b/drivers/spi/spi-bcm-qspi.c @@ -91,6 +91,7 @@ #define MSPI_MSPI_STATUS 0x020 #define MSPI_CPTQP 0x024 #define MSPI_SPCR3 0x028 +#define MSPI_REV 0x02c #define MSPI_TXRAM 0x040 #define MSPI_RXRAM 0x0c0 #define MSPI_CDRAM 0x140 @@ -217,6 +218,8 @@ struct bcm_qspi { struct bcm_qspi_dev_id *dev_ids; struct completion mspi_done; struct completion bspi_done; + u8 mspi_maj_rev; + u8 mspi_min_rev; }; static inline bool has_bspi(struct bcm_qspi *qspi) @@ -1190,8 +1193,35 @@ static const struct spi_controller_mem_ops bcm_qspi_mem_ops = { .exec_op = bcm_qspi_exec_mem_op, }; +struct bcm_qspi_data { + bool has_mspi_rev; +}; + +static const struct bcm_qspi_data bcm_qspi_no_rev_data = { + .has_mspi_rev = false, +}; + +static const struct bcm_qspi_data bcm_qspi_rev_data = { + .has_mspi_rev = true, +}; + static const struct of_device_id bcm_qspi_of_match[] = { - { .compatible = "brcm,spi-bcm-qspi" }, + { + .compatible = "brcm,spi-bcm7425-qspi", + .data = &bcm_qspi_no_rev_data, + }, + { + .compatible = "brcm,spi-bcm7429-qspi", + .data = &bcm_qspi_no_rev_data, + }, + { + .compatible = "brcm,spi-bcm7435-qspi", + .data = &bcm_qspi_no_rev_data, + }, + { + .compatible = "brcm,spi-bcm-qspi", + .data = &bcm_qspi_rev_data, + }, {}, }; MODULE_DEVICE_TABLE(of, bcm_qspi_of_match); @@ -1199,12 +1229,15 @@ MODULE_DEVICE_TABLE(of, bcm_qspi_of_match); int bcm_qspi_probe(struct platform_device *pdev, struct bcm_qspi_soc_intc *soc_intc) { + const struct of_device_id *of_id = NULL; + const struct bcm_qspi_data *data; struct device *dev = &pdev->dev; struct bcm_qspi *qspi; struct spi_master *master; struct resource *res; int irq, ret = 0, num_ints = 0; u32 val; + u32 rev = 0; const char *name = NULL; int num_irqs = ARRAY_SIZE(qspi_irq_tab); @@ -1212,9 +1245,12 @@ int bcm_qspi_probe(struct platform_device *pdev, if (!dev->of_node) return -ENODEV; - if (!of_match_node(bcm_qspi_of_match, dev->of_node)) + of_id = of_match_node(bcm_qspi_of_match, dev->of_node); + if (!of_id) return -ENODEV; + data = of_id->data; + master = spi_alloc_master(dev, sizeof(struct bcm_qspi)); if (!master) { dev_err(dev, "error allocating spi_master\n"); @@ -1351,6 +1387,16 @@ int bcm_qspi_probe(struct platform_device *pdev, qspi->base_clk = clk_get_rate(qspi->clk); qspi->max_speed_hz = qspi->base_clk / (QSPI_SPBR_MIN * 2); + if (data->has_mspi_rev) { + rev = bcm_qspi_read(qspi, MSPI, MSPI_REV); + /* some older revs do not have a MSPI_REV register */ + if ((rev & 0xff) == 0xff) + rev = 0; + } + + qspi->mspi_maj_rev = (rev >> 4) & 0xf; + qspi->mspi_min_rev = rev & 0xf; + bcm_qspi_hw_init(qspi); init_completion(&qspi->mspi_done); init_completion(&qspi->bspi_done); -- 2.7.4