Re: [dpdk-dev] [PATCH v2] i40e: workaround for XL710 performance

["Wu, Jingjing" <jingjing.wu@intel.com>]

> -----Original Message-----
> From: Zhang, Helin
> Sent: Monday, December 29, 2014 9:41 AM
> To: dev@dpdk.org
> Cc: nhorman@tuxdriver.com; Xu, Qian Q; Cao, Waterman; Lu, Patrick; Liu,
> Jijiang; Wu, Jingjing; Zhang, Helin
> Subject: [PATCH v2] i40e: workaround for XL710 performance
> 
> On XL710, performance number is far from the expectation on recent
> firmware versions, if promiscuous mode is disabled, or promiscuous mode is
> enabled and port MAC address is equal to the packet destination MAC
> address. The fix for this issue may not be integrated in the following
> firmware version. So the workaround in software driver is needed. For XL710,
> it needs to modify the initial values of 3 internal only registers, which are the
> same as X710.
> Note that the values for X710 and XL710 registers could be different, and the
> workaround can be removed when it is fixed in firmware in the future.
> 
> Signed-off-by: Helin Zhang <helin.zhang@intel.com>
> ---
>  lib/librte_pmd_i40e/i40e_ethdev.c | 44 ++++++++++++++++++++++++++---
> ----------
>  1 file changed, 30 insertions(+), 14 deletions(-)
> 
> v2 changes:
> * Supported modifying the address of 0x269FBC of XL710 during
>   initialization, to fix the minor performance gap to expectation.
>   That means XL710 can meet the performance expectation with this
>   workaround.
> 
> diff --git a/lib/librte_pmd_i40e/i40e_ethdev.c
> b/lib/librte_pmd_i40e/i40e_ethdev.c
> index b47a3d2..8982920 100644
> --- a/lib/librte_pmd_i40e/i40e_ethdev.c
> +++ b/lib/librte_pmd_i40e/i40e_ethdev.c
> @@ -5327,38 +5327,54 @@ i40e_debug_read_register(struct i40e_hw *hw,
> uint32_t addr, uint64_t *val)
> 
>  /*
>   * On X710, performance number is far from the expectation on recent
> firmware
> - * versions. The fix for this issue may not be integrated in the following
> + * versions; on XL710, performance number is also far from the
> + expectation on
> + * recent firmware versions, if promiscuous mode is disabled, or
> + promiscuous
> + * mode is enabled and port MAC address is equal to the packet
> + destination MAC
> + * address. The fix for this issue may not be integrated in the
> + following
>   * firmware version. So the workaround in software driver is needed. It
> needs
> - * to modify the initial values of 3 internal only registers. Note that the
> + * to modify the initial values of 3 internal only registers for both
> + X710 and
> + * XL710. Note that the values for X710 or XL710 could be different,
> + and the
>   * workaround can be removed when it is fixed in firmware in the future.
>   */
> -static void
> -i40e_configure_registers(struct i40e_hw *hw) -{
> +
> +/* For both X710 and XL710 */
> +#define I40E_GL_SWR_PRI_JOIN_MAP_0_VALUE 0x10000200
>  #define I40E_GL_SWR_PRI_JOIN_MAP_0       0x26CE00
> +
> +#define I40E_GL_SWR_PRI_JOIN_MAP_2_VALUE 0x011f0200
>  #define I40E_GL_SWR_PRI_JOIN_MAP_2       0x26CE08
> +
> +/* For X710 */
> +#define I40E_GL_SWR_PM_UP_THR_EF_VALUE   0x03030303
> +/* For XL710 */
> +#define I40E_GL_SWR_PM_UP_THR_SF_VALUE   0x06060606
>  #define I40E_GL_SWR_PM_UP_THR            0x269FBC
> -#define I40E_GL_SWR_PRI_JOIN_MAP_0_VALUE 0x10000200 -#define
> I40E_GL_SWR_PRI_JOIN_MAP_2_VALUE 0x011f0200
> -#define I40E_GL_SWR_PM_UP_THR_VALUE      0x03030303
> 
> -	static const struct {
> +static void
> +i40e_configure_registers(struct i40e_hw *hw) {
> +	static struct {
>  		uint32_t addr;
>  		uint64_t val;
>  	} reg_table[] = {
>  		{I40E_GL_SWR_PRI_JOIN_MAP_0,
> I40E_GL_SWR_PRI_JOIN_MAP_0_VALUE},
>  		{I40E_GL_SWR_PRI_JOIN_MAP_2,
> I40E_GL_SWR_PRI_JOIN_MAP_2_VALUE},
> -		{I40E_GL_SWR_PM_UP_THR,
> I40E_GL_SWR_PM_UP_THR_VALUE},
> +		{I40E_GL_SWR_PM_UP_THR, 0}, /* Compute value
> dynamically */
>  	};
>  	uint64_t reg;
>  	uint32_t i;
>  	int ret;
> 
> -	/* Below fix is for X710 only */
> -	if (i40e_is_40G_device(hw->device_id))
> -		return;
> -
>  	for (i = 0; i < RTE_DIM(reg_table); i++) {
> +		if (reg_table[i].addr == I40E_GL_SWR_PM_UP_THR) {
> +			if (i40e_is_40G_device(hw->device_id)) /* For XL710
> */
> +				reg_table[i].val =
> +
> 	I40E_GL_SWR_PM_UP_THR_SF_VALUE;
> +			else /* For X710 */
> +				reg_table[i].val =
> +
> 	I40E_GL_SWR_PM_UP_THR_EF_VALUE;
> +		}
> +
>  		ret = i40e_debug_read_register(hw, reg_table[i].addr, &reg);
>  		if (ret < 0) {
>  			PMD_DRV_LOG(ERR, "Failed to read from
> 0x%"PRIx32,
> --
> 1.9.3

Acked-by: Jingjing Wu <jingjing.wu@intel.com>