During early days of PCI quirks support ThunderX firmware did not provide
PNP0c02 node with PCI configuration space and PEM-specific register ranges.
This means that for legacy FW we are not reserving these resources and
cannot gather PEM-specific resources for further PEM initialization.
In order to support already deployed legacy FW calculate PEM-specific ranges
and provide resources reservation as fallback scenario into PEM driver when
we could not gather PEM reg base from ACPI tables.
Signed-off-by: Tomasz Nowicki <tn@xxxxxxxxxxxx>
Signed-off-by: Vadim Lomovtsev <Vadim.Lomovtsev@xxxxxxxxxxxxxxxxxx>
---
drivers/pci/host/pci-thunder-pem.c | 62 ++++++++++++++++++++++++++++++++++++--
1 file changed, 60 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/host/pci-thunder-pem.c b/drivers/pci/host/pci-thunder-pem.c
index e354010..cea5814 100644
--- a/drivers/pci/host/pci-thunder-pem.c
+++ b/drivers/pci/host/pci-thunder-pem.c
@@ -14,6 +14,7 @@
* Copyright (C) 2015 - 2016 Cavium, Inc.
*/
+#include <linux/bitfield.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/of_address.h>
@@ -319,6 +320,49 @@ static int thunder_pem_init(struct device *dev, struct pci_config_window *cfg,
#if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS)
+#define PEM_RES_BASE 0x87e0c0000000UL
+#define PEM_NODE_MASK GENMASK(45, 44)
+#define PEM_INDX_MASK GENMASK(26, 24)
+#define PEM_MIN_DOM_IN_NODE 4
+#define PEM_MAX_DOM_IN_NODE 10
+
+static void thunder_pem_reserve_range(struct device *dev, int seg,
+ struct resource *r)
+{
+ resource_size_t start = r->start, end = r->end;
+ struct resource *res;
+ const char *regionid;
+
+ regionid = kasprintf(GFP_KERNEL, "PEM RC:%d", seg);
+ if (!regionid)
+ return;
+
+ res = request_mem_region(start, end - start + 1, regionid);
+ if (res)
+ res->flags &= ~IORESOURCE_BUSY;
+ else
+ kfree(regionid);
+
+ dev_info(dev, "%pR %s reserved\n", r,
+ res ? "has been" : "could not be");
+}
+
+static void thunder_pem_legacy_fw(struct acpi_pci_root *root,
+ struct resource *res_pem)
+{
+ int node = acpi_get_node(root->device->handle);
+ int index;
+
+ if (node == NUMA_NO_NODE)
+ node = 0;
+
+ index = root->segment - PEM_MIN_DOM_IN_NODE;
+ index -= node * PEM_MAX_DOM_IN_NODE;
+ res_pem->start = PEM_RES_BASE | FIELD_PREP(PEM_NODE_MASK, node) |
+ FIELD_PREP(PEM_INDX_MASK, index);
+ res_pem->flags = IORESOURCE_MEM;
+}
+
static int thunder_pem_acpi_init(struct pci_config_window *cfg)
{
struct device *dev = cfg->parent;
@@ -332,9 +376,23 @@ static int thunder_pem_acpi_init(struct pci_config_window *cfg)
return -ENOMEM;
ret = acpi_get_rc_resources(dev, "CAVA02B", root->segment, res_pem);
+
+ /*
+ * If we fail to gather resources it means that we run with old
+ * FW where we need to calculate PEM-specific resources manually.
+ */
if (ret) {
- dev_err(dev, "can't get rc base address\n");
- return ret;
+ thunder_pem_legacy_fw(root, res_pem);
+ /*
+ * Reserve 64K size PEM specific resources. The full 16M range
+ * size is required for thunder_pem_init() call.
+ */
+ res_pem->end = res_pem->start + SZ_64K - 1;
+ thunder_pem_reserve_range(dev, root->segment, res_pem);
+ res_pem->end = res_pem->start + SZ_16M - 1;
+
+ /* Reserve PCI configuration space as well. */
+ thunder_pem_reserve_range(dev, root->segment, &cfg->res);
}
return thunder_pem_init(dev, cfg, res_pem);
--
2.7.4
