On 29-Oct-17 3:11 PM, Vidya Sagar wrote:
>
>
> On Saturday 28 October 2017 12:59 AM, Manikanta Maddireddy wrote:
>> This patch ensures that DL sends pending ACKs and update FC packets when
>> link is idle instead of waiting for timers to expire which improves PCIe
>> bandwidth.
>>
>> Signed-off-by: Manikanta Maddireddy <mmaddireddy@xxxxxxxxxx>
>> ---
>> drivers/pci/host/pci-tegra.c | 15 ++++++++++++++-
>> 1 file changed, 14 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c
>> index af34daf3c6a2..27a8211c48b2 100644
>> --- a/drivers/pci/host/pci-tegra.c
>> +++ b/drivers/pci/host/pci-tegra.c
>> @@ -209,7 +209,9 @@
>> #define RP_ECTL_6_R2_RX_EQ_CTRL_H_1C_MASK 0xffffffff
>> #define RP_VEND_XP 0x00000f00
>> -#define RP_VEND_XP_DL_UP (1 << 30)
>> +#define RP_VEND_XP_DL_UP (1 << 30)
>> +#define RP_VEND_XP_OPPORTUNISTIC_ACK (1 << 27)
>> +#define RP_VEND_XP_OPPORTUNISTIC_UPDATEFC (1 << 28)
>>
> BIT macro is preferred here.
Left shift is used everywhere, so to be inline with that I used same format
>> #define RP_VEND_CTL1 0xf48
>> #define RP_VEND_CTL1_ERPT (1 << 13)
>> @@ -2147,6 +2149,16 @@ static void tegra_pcie_enable_rp_features(struct tegra_pcie_port *port)
>> writel(value, port->base + RP_VEND_CTL1);
>> }
>> +static void tegra_pcie_apply_sw_fixup(struct tegra_pcie_port *port)
>> +{
>> + unsigned long value;
>> +
>> + /* Optimal settings to enhance bandwidth */
>> + value = readl(port->base + RP_VEND_XP);
>> + value |= RP_VEND_XP_OPPORTUNISTIC_ACK;
>> + value |= RP_VEND_XP_OPPORTUNISTIC_UPDATEFC;
>> + writel(value, port->base + RP_VEND_XP);
>> +}
>> /*
>> * FIXME: If there are no PCIe cards attached, then calling this function
>> * can result in the increase of the bootup time as there are big timeout
>> @@ -2215,6 +2227,7 @@ static void tegra_pcie_enable_ports(struct tegra_pcie *pcie)
>> if (soc->program_ectl_settings)
>> tegra_pcie_program_ectl_settings(port);
>> tegra_pcie_enable_rp_features(port);
>> + tegra_pcie_apply_sw_fixup(port);
>> }
>> /* take the PCIe interface module out of reset */
>
