PCI: rcar: Allow DT to override default window settings
If the DTB specifies dma-ranges, use those values. Otherwise, default to
the values that were previously hardcoded into the driver.
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
diff --git a/drivers/pci/host/pci-rcar-gen2.c b/drivers/pci/host/pci-rcar-gen2.c
index c4f64bf..6295116 100644
--- a/drivers/pci/host/pci-rcar-gen2.c
+++ b/drivers/pci/host/pci-rcar-gen2.c
@@ -15,6 +15,7 @@
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
@@ -102,6 +103,8 @@
unsigned busnr;
int irq;
unsigned long window_size;
+ unsigned long window_addr;
+ unsigned long window_pci;
};
/* PCI configuration space operations */
@@ -239,8 +242,8 @@
RCAR_PCI_ARBITER_PCIBP_MODE;
iowrite32(val, reg + RCAR_PCI_ARBITER_CTR_REG);
- /* PCI-AHB mapping: 0x40000000 base */
- iowrite32(0x40000000 | RCAR_PCIAHB_PREFETCH16,
+ /* PCI-AHB mapping */
+ iowrite32(priv->window_addr | RCAR_PCIAHB_PREFETCH16,
reg + RCAR_PCIAHB_WIN1_CTR_REG);
/* AHB-PCI mapping: OHCI/EHCI registers */
@@ -251,7 +254,7 @@
iowrite32(RCAR_AHBPCI_WIN1_HOST | RCAR_AHBPCI_WIN_CTR_CFG,
reg + RCAR_AHBPCI_WIN1_CTR_REG);
/* Set PCI-AHB Window1 address */
- iowrite32(0x40000000 | PCI_BASE_ADDRESS_MEM_PREFETCH,
+ iowrite32(priv->window_pci | PCI_BASE_ADDRESS_MEM_PREFETCH,
reg + PCI_BASE_ADDRESS_1);
/* Set AHB-PCI bridge PCI communication area address */
val = priv->cfg_res->start + RCAR_AHBPCI_PCICOM_OFFSET;
@@ -284,6 +287,64 @@
.write = pci_generic_config_write,
};
+static int pci_dma_range_parser_init(struct of_pci_range_parser *parser,
+ struct device_node *node)
+{
+ const int na = 3, ns = 2;
+ int rlen;
+
+ parser->node = node;
+ parser->pna = of_n_addr_cells(node);
+ parser->np = parser->pna + na + ns;
+
+ parser->range = of_get_property(node, "dma-ranges", &rlen);
+ if (!parser->range)
+ return -ENOENT;
+
+ parser->end = parser->range + rlen / sizeof(__be32);
+ return 0;
+}
+
+static int rcar_pci_parse_map_dma_ranges(struct rcar_pci_priv *pci,
+ struct device_node *np)
+{
+ struct of_pci_range range;
+ struct of_pci_range_parser parser;
+ int index = 0;
+
+ /* Failure to parse is ok as we fall back to defaults */
+ if (pci_dma_range_parser_init(&parser, np))
+ return 0;
+
+ /* Get the dma-ranges from DT */
+ for_each_of_pci_range(&parser, &range) {
+ /* Hardware only allows one inbound 32-bit range */
+ if (index)
+ return -EINVAL;
+
+ pci->window_addr = (unsigned long)range.cpu_addr;
+ pci->window_pci = (unsigned long)range.pci_addr;
+ pci->window_size = (unsigned long)range.size;
+
+ /* Catch HW limitations */
+ if (!(range.flags & IORESOURCE_PREFETCH)) {
+ dev_err(pci->dev, "window must be prefetchable\n");
+ return -EINVAL;
+ }
+ if (pci->window_addr) {
+ u32 lowaddr = 1 << (ffs(pci->window_addr) - 1);
+
+ if (lowaddr < pci->window_size) {
+ dev_err(pci->dev, "invalid window size/addr\n");
+ return -EINVAL;
+ }
+ }
+ index++;
+ }
+
+ return 0;
+}
+
static int rcar_pci_probe(struct platform_device *pdev)
{
struct resource *cfg_res, *mem_res;
@@ -329,6 +390,9 @@
return priv->irq;
}
+ /* default window addr and size if not specified in DT */
+ priv->window_addr = 0x40000000;
+ priv->window_pci = 0x40000000;
priv->window_size = SZ_1G;
if (pdev->dev.of_node) {
@@ -344,6 +408,12 @@
priv->busnr = busnr.start;
if (busnr.end != busnr.start)
dev_warn(&pdev->dev, "only one bus number supported\n");
+
+ ret = rcar_pci_parse_map_dma_ranges(priv, pdev->dev.of_node);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to parse dma-range\n");
+ return ret;
+ }
} else {
priv->busnr = pdev->id;
}