From: Gustavo Pimentel Date: Mon, 14 May 2018 15:09:49 +0000 (+0100) Subject: PCI: dwc: Small computation improvement X-Git-Tag: v4.18-rc1~106^2~12^2~11 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6995de2168edc6e58a350e7eb76e02dd191b64f4;p=thirdparty%2Fkernel%2Flinux.git PCI: dwc: Small computation improvement 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 Signed-off-by: Lorenzo Pieralisi Acked-by: Jingoo Han Acked-by: Joao Pinto --- diff --git a/drivers/pci/dwc/pcie-designware-host.c b/drivers/pci/dwc/pcie-designware-host.c index 5a23f782851a0..fc55fde8742e2 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;