--- /dev/null
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Subject: [PATCH] bcma: get SoC device struct & copy its DMA params to the
+ subdevices
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+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")
+Cc: linux-mips@linux-mips.org
+Cc: Christoph Hellwig <hch@lst.de>
+Cc: Linus Walleij <linus.walleij@linaro.org>
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+---
+
+--- a/drivers/bcma/host_soc.c
++++ b/drivers/bcma/host_soc.c
+@@ -191,6 +191,8 @@ int __init bcma_host_soc_init(struct bcm
+ 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)
+--- a/drivers/bcma/main.c
++++ b/drivers/bcma/main.c
+@@ -236,12 +236,16 @@ EXPORT_SYMBOL(bcma_core_irq);
+
+ void bcma_prepare_core(struct bcma_bus *bus, struct bcma_device *core)
+ {
++ struct device *dev = &core->dev;
++
+ core->dev.release = bcma_release_core_dev;
+ core->dev.bus = &bcma_bus_type;
+ dev_set_name(&core->dev, "bcma%d:%d", bus->num, core->core_index);
+ core->dev.parent = bus->dev;
+- if (bus->dev)
++ if (bus->dev) {
+ bcma_of_fill_device(bus->dev, core);
++ dma_coerce_mask_and_coherent(dev, bus->dev->coherent_dma_mask);
++ }
+
+ switch (bus->hosttype) {
+ case BCMA_HOSTTYPE_PCI:
+--- a/include/linux/bcma/bcma_soc.h
++++ b/include/linux/bcma/bcma_soc.h
+@@ -6,6 +6,7 @@
+
+ struct bcma_soc {
+ struct bcma_bus bus;
++ struct device *dev;
+ };
+
+ int __init bcma_host_soc_register(struct bcma_soc *soc);