On SoCs the sprom is stored in the nvram in a special partition on the
flash chip. The nvram contains the sprom for the main bus, but
sometimes also for a pci devices using bcma. This patch makes it
possible for the arch code to register a function to fetch the needed
sprom from the nvram and provide it to the bcma code.
Signed-off-by: Hauke Mehrtens <hauke@xxxxxxxxxx>
---
drivers/bcma/sprom.c | 75 ++++++++++++++++++++++++++++++++++++++++-----
include/linux/bcma/bcma.h | 6 +++
2 files changed, 73 insertions(+), 8 deletions(-)
diff --git a/drivers/bcma/sprom.c b/drivers/bcma/sprom.c
index ca77525..73c204d 100644
--- a/drivers/bcma/sprom.c
+++ b/drivers/bcma/sprom.c
@@ -14,6 +14,45 @@
#include <linux/dma-mapping.h>
#include <linux/slab.h>
+static int(*get_fallback_sprom)(struct bcma_bus *dev, struct ssb_sprom *out);
+
+/**
+ * bcma_arch_register_fallback_sprom - Registers a method providing a
+ * fallback SPROM if no SPROM is found.
+ *
+ * @sprom_callback: The callback function.
+ *
+ * With this function the architecture implementation may register a
+ * callback handler which fills the SPROM data structure. The fallback is
+ * used for PCI based BCMA devices, where no valid SPROM can be found
+ * in the shadow registers and to provide the SPROM for SoCs where BCMA is
+ * to controll the system bus.
+ *
+ * This function is useful for weird architectures that have a half-assed
+ * BCMA device hardwired to their PCI bus.
+ *
+ * This function is available for architecture code, only. So it is not
+ * exported.
+ */
+int bcma_arch_register_fallback_sprom(int (*sprom_callback)(struct bcma_bus *bus,
+ struct ssb_sprom *out))
+{
+ if (get_fallback_sprom)
+ return -EEXIST;
+ get_fallback_sprom = sprom_callback;
+
+ return 0;
+}
+
+static int bcma_fill_sprom_with_fallback(struct bcma_bus *bus,
+ struct ssb_sprom *out)
+{
+ if (!get_fallback_sprom)
+ return -ENOENT;
+
+ return get_fallback_sprom(bus, out);
+}
+
/**************************************************
* R/W ops.
**************************************************/
@@ -246,23 +285,43 @@ static void bcma_sprom_extract_r8(struct bcma_bus *bus, const u16 *sprom)
SSB_SROM8_FEM_ANTSWLUT_SHIFT);
}
+static bool bcma_is_sprom_available(struct bcma_bus *bus)
+{
+ u32 sromctrl;
+
+ if (!(bus->drv_cc.capabilities & BCMA_CC_CAP_SPROM))
+ return false;
+
+ if (bus->drv_cc.core->id.rev >= 32) {
+ sromctrl = bcma_read32(bus->drv_cc.core, BCMA_CC_SROM_CONTROL);
+ return sromctrl & BCMA_CC_SROM_CONTROL_PRESENT;
+ }
+ return true;
+}
+
int bcma_sprom_get(struct bcma_bus *bus)
{
u16 offset;
u16 *sprom;
- u32 sromctrl;
int err = 0;
if (!bus->drv_cc.core)
return -EOPNOTSUPP;
- if (!(bus->drv_cc.capabilities & BCMA_CC_CAP_SPROM))
- return -ENOENT;
-
- if (bus->drv_cc.core->id.rev >= 32) {
- sromctrl = bcma_read32(bus->drv_cc.core, BCMA_CC_SROM_CONTROL);
- if (!(sromctrl & BCMA_CC_SROM_CONTROL_PRESENT))
- return -ENOENT;
+ if (!bcma_is_sprom_available(bus)) {
+ /*
+ * Maybe there is no SPROM on the device?
+ * Now we ask the arch code if there is some sprom
+ * available for this device in some other storage.
+ */
+ err = bcma_fill_sprom_with_fallback(bus, &bus->sprom);
+ if (err) {
+ pr_warn("Using fallback SPROM failed (err %d)\n", err);
+ } else {
+ pr_debug("Using SPROM revision %d provided by"
+ " platform.\n", bus->sprom.revision);
+ return 0;
+ }
}
sprom = kcalloc(SSB_SPROMSIZE_WORDS_R4, sizeof(u16),
diff --git a/include/linux/bcma/bcma.h b/include/linux/bcma/bcma.h
index 46bbd08..5af9a07 100644
--- a/include/linux/bcma/bcma.h
+++ b/include/linux/bcma/bcma.h
@@ -176,6 +176,12 @@ int __bcma_driver_register(struct bcma_driver *drv, struct module *owner);
extern void bcma_driver_unregister(struct bcma_driver *drv);
+/* Set a fallback SPROM.
+ * See kdoc at the function definition for complete documentation. */
+extern int bcma_arch_register_fallback_sprom(
+ int (*sprom_callback)(struct bcma_bus *bus,
+ struct ssb_sprom *out));
+
struct bcma_bus {
/* The MMIO area. */
void __iomem *mmio;
--
1.7.5.4
--
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