From: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Date: Mon, 14 May 2018 16:09:49 +0100
Subject: PCI: dwc: Small computation improvement
Git-commit: 6995de2168edc6e58a350e7eb76e02dd191b64f4
Patch-mainline: v4.18-rc1
References: fate#326536, fate#326532
Replace a division by 2 operation for a right shift rotation of 1 bit.
Probably any recent and decent compiler does this kind of substitution
in order to improve code performance. Nevertheless it's a coding good
practice whenever there is a division / multiplication by multiple of 2
to replace it by the equivalent operation in this case, the shift
rotation.
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Acked-by: Joao Pinto <jpinto@synopsys.com>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
---
drivers/pci/dwc/pcie-designware-host.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/pci/dwc/pcie-designware-host.c b/drivers/pci/dwc/pcie-designware-host.c
index 5a23f782851a..fc55fde8742e 100644
--- a/drivers/pci/dwc/pcie-designware-host.c
+++ b/drivers/pci/dwc/pcie-designware-host.c
@@ -332,8 +332,8 @@ int dw_pcie_host_init(struct pcie_port *pp)
cfg_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "config");
if (cfg_res) {
- pp->cfg0_size = resource_size(cfg_res) / 2;
- pp->cfg1_size = resource_size(cfg_res) / 2;
+ pp->cfg0_size = resource_size(cfg_res) >> 1;
+ pp->cfg1_size = resource_size(cfg_res) >> 1;
pp->cfg0_base = cfg_res->start;
pp->cfg1_base = cfg_res->start + pp->cfg0_size;
} else if (!pp->va_cfg0_base) {
@@ -377,8 +377,8 @@ int dw_pcie_host_init(struct pcie_port *pp)
break;
case 0:
pp->cfg = win->res;
- pp->cfg0_size = resource_size(pp->cfg) / 2;
- pp->cfg1_size = resource_size(pp->cfg) / 2;
+ pp->cfg0_size = resource_size(pp->cfg) >> 1;
+ pp->cfg1_size = resource_size(pp->cfg) >> 1;
pp->cfg0_base = pp->cfg->start;
pp->cfg1_base = pp->cfg->start + pp->cfg0_size;
break;
--
2.11.0