PCI: rcar: Poll more often in rcar_pcie_wait_for_dl()

The data link active signal usually takes ~20 uSec to be asserted, poll
the bit more often to avoid useless delays in this function.

Use udelay() instead of usleep() for such a small delay as suggested by
the timer documentation.
Signed-off-by: NMarek Vasut <marek.vasut+renesas@gmail.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NSimon Horman <horms+renesas@verge.net.au>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Cc: Simon Horman <horms+renesas@verge.net.au>
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: linux-renesas-soc@vger.kernel.org

drivers/pci/host/pcie-rcar.c

@@ -546,13 +546,14 @@ static int rcar_pcie_wait_for_phyrdy(struct rcar_pcie *pcie)
 
 static int rcar_pcie_wait_for_dl(struct rcar_pcie *pcie)
 {
-	unsigned int timeout = 10;
+	unsigned int timeout = 10000;
 
 	while (timeout--) {
 		if ((rcar_pci_read_reg(pcie, PCIETSTR) & DATA_LINK_ACTIVE))
 			return 0;
 
-		msleep(5);
+		udelay(5);
+		cpu_relax();
 	}
 
 	return -ETIMEDOUT;