Re: [PATCH v4 2/4] Watchdog: sp5100_tco: Refactor MMIO base address initialization
From: Guenter Roeck
Date: Tue Feb 01 2022 - 17:36:42 EST
On 2/1/22 12:32, Terry Bowman wrote:
On 2/1/22 10:46, Terry Bowman wrote:
On 2/1/22 09:31, Guenter Roeck wrote:
On 1/30/22 11:12, Terry Bowman wrote:
Combine MMIO base address and alternate base address detection. Combine
based on layout type. This will simplify the function by eliminating
a switch case.
Move existing request/release code into functions. This currently only
supports port I/O request/release. The move into a separate function
will make it ready for adding MMIO region support.
Co-developed-by: Robert Richter <rrichter@xxxxxxx>
Signed-off-by: Robert Richter <rrichter@xxxxxxx>
Signed-off-by: Terry Bowman <terry.bowman@xxxxxxx>
Tested-by: Jean Delvare <jdelvare@xxxxxxx>
Reviewed-by: Jean Delvare <jdelvare@xxxxxxx>
---
drivers/watchdog/sp5100_tco.c | 155 ++++++++++++++++++----------------
drivers/watchdog/sp5100_tco.h | 1 +
2 files changed, 82 insertions(+), 74 deletions(-)
diff --git a/drivers/watchdog/sp5100_tco.c b/drivers/watchdog/sp5100_tco.c
index b365bbc9ac36..16e122d5045e 100644
--- a/drivers/watchdog/sp5100_tco.c
+++ b/drivers/watchdog/sp5100_tco.c
@@ -223,6 +223,55 @@ static u32 sp5100_tco_read_pm_reg32(u8 index)
return val;
}
+static u32 sp5100_tco_request_region(struct device *dev,
+ u32 mmio_addr,
+ const char *dev_name)
+{
+ if (!devm_request_mem_region(dev, mmio_addr, SP5100_WDT_MEM_MAP_SIZE,
+ dev_name)) {
+ dev_dbg(dev, "MMIO address 0x%08x already in use\n", mmio_addr);
+ return 0;
+ }
+
+ return mmio_addr;
+}
+
+static u32 sp5100_tco_prepare_base(struct sp5100_tco *tco,
+ u32 mmio_addr,
+ u32 alt_mmio_addr,
+ const char *dev_name)
+{
+ struct device *dev = tco->wdd.parent;
+
+ dev_dbg(dev, "Got 0x%08x from SBResource_MMIO register\n", mmio_addr);
+
+ if (!mmio_addr && !alt_mmio_addr)
+ return -ENODEV;
+
+ /* Check for MMIO address and alternate MMIO address conflicts */
+ if (mmio_addr)
+ mmio_addr = sp5100_tco_request_region(dev, mmio_addr, dev_name);
+
+ if (!mmio_addr && alt_mmio_addr)
+ mmio_addr = sp5100_tco_request_region(dev, alt_mmio_addr, dev_name);
+
+ if (!mmio_addr) {
+ dev_err(dev, "Failed to reserve MMIO or alternate MMIO region\n");
+ return -EBUSY;
+ }
+
+ tco->tcobase = devm_ioremap(dev, mmio_addr, SP5100_WDT_MEM_MAP_SIZE);
+ if (!tco->tcobase) {
+ dev_err(dev, "MMIO address 0x%08x failed mapping\n", mmio_addr);
+ devm_release_mem_region(dev, mmio_addr, SP5100_WDT_MEM_MAP_SIZE);
+ return -ENOMEM;
+ }
+
+ dev_info(dev, "Using 0x%08x for watchdog MMIO address\n", tco->tcobase);
+
I know this is the same as the old code, but I think it would make sense to change
this as suggested by 0-day and use %px instead.
Thanks,
Guenter
Hi Guenter,
This line was changed in v4 and should be reverted. It should be using the mmio_addr
physical address with '0x%08x' formatting instead of tco->tcobase. This would be:
dev_info(dev, "Using 0x%08x for watchdog MMIO address\n", mmio_addr);
The dmesg then provides:
[ 5.972921] sp5100_tco: SP5100/SB800 TCO WatchDog Timer Driver
[ 5.978238] sp5100-tco sp5100-tco: Using 0xfeb00000 for watchdog MMIO address
[ 5.978252] sp5100-tco sp5100-tco: Watchdog hardware is disabled
Do your agree?
Yes. Displaying the mapped address has zero if any value.
Guenter