On 15-Apr-19 6:55 PM, Thierry Reding wrote:
> On Thu, Apr 11, 2019 at 10:33:42PM +0530, Manikanta Maddireddy wrote:
>> Use switch statements in tegra_pcie_isr() for better code readability.
>>
>> Signed-off-by: Manikanta Maddireddy <mmaddireddy@xxxxxxxxxx>
>> ---
>> drivers/pci/controller/pci-tegra.c | 37 ++++++++++++++++--------------
>> 1 file changed, 20 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c
>> index cdaaf13a9fd7..cf2715065a53 100644
>> --- a/drivers/pci/controller/pci-tegra.c
>> +++ b/drivers/pci/controller/pci-tegra.c
>> @@ -842,36 +842,39 @@ static irqreturn_t tegra_pcie_isr(int irq, void *arg)
>> };
>> struct tegra_pcie *pcie = arg;
>> struct device *dev = pcie->dev;
>> - u32 code, signature;
>> + u32 code, signature, fpci;
>> + u64 address;
>>
>> code = afi_readl(pcie, AFI_INTR_CODE) & AFI_INTR_CODE_MASK;
>> signature = afi_readl(pcie, AFI_INTR_SIGNATURE);
>> afi_writel(pcie, 0, AFI_INTR_CODE);
>>
>> - if (code == AFI_INTR_LEGACY)
>> - return IRQ_NONE;
>> -
>> if (code >= ARRAY_SIZE(err_msg))
>> - code = 0;
>> + return IRQ_NONE;
>>
>> + switch (code) {
>> + case AFI_INTR_LEGACY:
>> + return IRQ_NONE;
>> /*
>> * do not pollute kernel log with master abort reports since they
>> * happen a lot during enumeration
>> */
>> - if (code == AFI_INTR_MASTER_ABORT)
>> + case AFI_INTR_MASTER_ABORT:
>> dev_dbg(dev, "%s, signature: %08x\n", err_msg[code], signature);
>> - else
>> + fpci = afi_readl(pcie, AFI_UPPER_FPCI_ADDRESS) & 0xff;
>> + address = (u64)fpci << 32 | (signature & 0xfffffffc);
>> + dev_dbg(dev, " FPCI address: %10llx\n", address);
>> + break;
>> + case AFI_INTR_TARGET_ABORT:
>> + case AFI_INTR_FPCI_DECODE_ERROR:
>> dev_err(dev, "%s, signature: %08x\n", err_msg[code], signature);
>> -
>> - if (code == AFI_INTR_TARGET_ABORT || code == AFI_INTR_MASTER_ABORT ||
>> - code == AFI_INTR_FPCI_DECODE_ERROR) {
>> - u32 fpci = afi_readl(pcie, AFI_UPPER_FPCI_ADDRESS) & 0xff;
>> - u64 address = (u64)fpci << 32 | (signature & 0xfffffffc);
>> -
>> - if (code == AFI_INTR_MASTER_ABORT)
>> - dev_dbg(dev, " FPCI address: %10llx\n", address);
>> - else
>> - dev_err(dev, " FPCI address: %10llx\n", address);
>> + fpci = afi_readl(pcie, AFI_UPPER_FPCI_ADDRESS) & 0xff;
>> + address = (u64)fpci << 32 | (signature & 0xfffffffc);
>> + dev_err(dev, " FPCI address: %10llx\n", address);
>> + break;
>> + default:
>> + dev_err(dev, "%s, signature: %08x\n", err_msg[code], signature);
>> + break;
>> }
>>
>> return IRQ_HANDLED;
> I don't think this improves readability. It does duplicate some code and
> is actually longer than the previous variant, so I don't think this adds
> value.
>
> Thierry
There is multiple conditions check in single "if" statement and there is if-else statement
inside "if", so I felt switch case makes it more clear. I agree there is duplicate code.
Manikanta
