bcma: add support for sprom not found on the device

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@hauke-m.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Hauke Mehrtens 2012-02-28 00:56:10 +01:00 committed by John W. Linville
parent 1c9351cf21
commit a027237a56
2 changed files with 75 additions and 8 deletions

View File

@ -2,6 +2,8 @@
* Broadcom specific AMBA
* SPROM reading
*
* Copyright 2011, 2012, Hauke Mehrtens <hauke@hauke-m.de>
*
* Licensed under the GNU/GPL. See COPYING for details.
*/
@ -14,6 +16,45 @@
#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 +287,43 @@ 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),

View File

@ -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;