From: Rafał Miłecki <rafal@xxxxxxxxxx> For bus devices to be fully usable it's required to set their DMA parameters. For years it has been missing and remained unnoticed because of mips_dma_alloc_coherent() silently handling the empty coherent_dma_mask. Kernel 4.19 came with a lot of DMA changes and caused a regression on the bcm47xx. Starting with the commit f8c55dc6e828 ("MIPS: use generic dma noncoherent ops for simple noncoherent platforms") DMA coherent allocations just fail. Example: [ 1.114914] bgmac_bcma bcma0:2: Allocation of TX ring 0x200 failed [ 1.121215] bgmac_bcma bcma0:2: Unable to alloc memory for DMA [ 1.127626] bgmac_bcma: probe of bcma0:2 failed with error -12 [ 1.133838] bgmac_bcma: Broadcom 47xx GBit MAC driver loaded This change fixes above regression in addition to the MIPS bcm47xx commit 321c46b91550 ("MIPS: BCM47XX: Setup struct device for the SoC"). It also fixes another *old* GPIO regression caused by a parent pointing to the NULL: [ 0.157054] missing gpiochip .dev parent pointer [ 0.157287] bcma: bus0: Error registering GPIO driver: -22 introduced by the commit 74f4e0cc6108 ("bcma: switch GPIO portions to use GPIOLIB_IRQCHIP"). Fixes: f8c55dc6e828 ("MIPS: use generic dma noncoherent ops for simple noncoherent platforms") Fixes: 74f4e0cc6108 ("bcma: switch GPIO portions to use GPIOLIB_IRQCHIP") Signed-off-by: Rafał Miłecki <rafal@xxxxxxxxxx> Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxxx Cc: Christoph Hellwig <hch@xxxxxx> Cc: Linus Walleij <linus.walleij@xxxxxxxxxx> --- Christoph, I don't know if this is what you had in mind. I am also not sure if we should have the bcma_bus_type implement .dma_configure and set it to platform_dma_configure? drivers/bcma/host_soc.c | 2 ++ drivers/bcma/main.c | 2 ++ 2 files changed, 4 insertions(+) diff --git a/drivers/bcma/host_soc.c b/drivers/bcma/host_soc.c index 90d5bdc12e03..fd2e8ff17c76 100644 --- a/drivers/bcma/host_soc.c +++ b/drivers/bcma/host_soc.c @@ -191,6 +191,8 @@ int __init bcma_host_soc_init(struct bcma_soc *soc) struct bcma_bus *bus = &soc->bus; int err; + bus->dev = soc->dev; + /* Scan bus and initialize it */ err = bcma_bus_early_register(bus); if (err) diff --git a/drivers/bcma/main.c b/drivers/bcma/main.c index 8e7ca3e4c8c4..6793c2ff60fd 100644 --- a/drivers/bcma/main.c +++ b/drivers/bcma/main.c @@ -253,6 +253,8 @@ void bcma_prepare_core(struct bcma_bus *bus, struct bcma_device *core) if (IS_ENABLED(CONFIG_OF) && bus->dev) { core->dma_dev = bus->dev; } else { + if (!core->dev.coherent_dma_mask) + core->dev.coherent_dma_mask = DMA_BIT_MASK(32); core->dev.dma_mask = &core->dev.coherent_dma_mask; core->dma_dev = &core->dev; } -- 2.25.1