mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-27 09:12:39 +00:00
55 lines
1.8 KiB
Diff
55 lines
1.8 KiB
Diff
|
From 7fbcb5da811be7d47468417c7795405058abb3da Mon Sep 17 00:00:00 2001
|
||
|
|
From: Remi Pommarel <repk@triplefau.lt>
|
||
|
|
Date: Fri, 27 Sep 2019 10:55:02 +0200
|
||
|
|
Subject: [PATCH] PCI: aardvark: Don't rely on jiffies while holding spinlock
|
||
|
|
|
||
|
|
advk_pcie_wait_pio() can be called while holding a spinlock (from
|
||
|
|
pci_bus_read_config_dword()), then depends on jiffies in order to
|
||
|
|
timeout while polling on PIO state registers. In the case the PIO
|
||
|
|
transaction failed, the timeout will never happen and will also cause
|
||
|
|
the cpu to stall.
|
||
|
|
|
||
|
|
This decrements a variable and wait instead of using jiffies.
|
||
|
|
|
||
|
|
Signed-off-by: Remi Pommarel <repk@triplefau.lt>
|
||
|
|
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
|
||
|
|
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
|
||
|
|
Acked-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
|
||
|
|
---
|
||
|
|
drivers/pci/controller/pci-aardvark.c | 10 +++++-----
|
||
|
|
1 file changed, 5 insertions(+), 5 deletions(-)
|
||
|
|
|
||
|
|
--- a/drivers/pci/controller/pci-aardvark.c
|
||
|
|
+++ b/drivers/pci/controller/pci-aardvark.c
|
||
|
|
@@ -175,7 +175,8 @@
|
||
|
|
(PCIE_CONF_BUS(bus) | PCIE_CONF_DEV(PCI_SLOT(devfn)) | \
|
||
|
|
PCIE_CONF_FUNC(PCI_FUNC(devfn)) | PCIE_CONF_REG(where))
|
||
|
|
|
||
|
|
-#define PIO_TIMEOUT_MS 1
|
||
|
|
+#define PIO_RETRY_CNT 500
|
||
|
|
+#define PIO_RETRY_DELAY 2 /* 2 us*/
|
||
|
|
|
||
|
|
#define LINK_WAIT_MAX_RETRIES 10
|
||
|
|
#define LINK_WAIT_USLEEP_MIN 90000
|
||
|
|
@@ -400,17 +401,16 @@ static void advk_pcie_check_pio_status(s
|
||
|
|
static int advk_pcie_wait_pio(struct advk_pcie *pcie)
|
||
|
|
{
|
||
|
|
struct device *dev = &pcie->pdev->dev;
|
||
|
|
- unsigned long timeout;
|
||
|
|
+ int i;
|
||
|
|
|
||
|
|
- timeout = jiffies + msecs_to_jiffies(PIO_TIMEOUT_MS);
|
||
|
|
-
|
||
|
|
- while (time_before(jiffies, timeout)) {
|
||
|
|
+ for (i = 0; i < PIO_RETRY_CNT; i++) {
|
||
|
|
u32 start, isr;
|
||
|
|
|
||
|
|
start = advk_readl(pcie, PIO_START);
|
||
|
|
isr = advk_readl(pcie, PIO_ISR);
|
||
|
|
if (!start && isr)
|
||
|
|
return 0;
|
||
|
|
+ udelay(PIO_RETRY_DELAY);
|
||
|
|
}
|
||
|
|
|
||
|
|
dev_err(dev, "config read/write timed out\n");
|