On 12-Oct-20 9:09 AM, Wang, Haiyue wrote:
Hi Liang,
-----Original Message-----
From: Burakov, Anatoly <[email protected]>
Sent: Saturday, October 10, 2020 00:02
To: [email protected]
Cc: Ma, Liang J <[email protected]>; Guo, Jia <[email protected]>; Wang,
Haiyue
<[email protected]>; Hunt, David <[email protected]>; Ananyev, Konstantin
<[email protected]>; [email protected]; Richardson, Bruce
<[email protected]>;
[email protected]; McDaniel, Timothy <[email protected]>; Eads, Gage
<[email protected]>;
Macnamara, Chris <[email protected]>
Subject: [PATCH v5 06/10] net/ixgbe: implement power management API
From: Liang Ma <[email protected]>
Implement support for the power management API by implementing a
`get_wake_addr` function that will return an address of an RX ring's
status bit.
Signed-off-by: Anatoly Burakov <[email protected]>
Signed-off-by: Liang Ma <[email protected]>
---
drivers/net/ixgbe/ixgbe_ethdev.c | 1 +
drivers/net/ixgbe/ixgbe_rxtx.c | 22 ++++++++++++++++++++++
drivers/net/ixgbe/ixgbe_rxtx.h | 2 ++
3 files changed, 25 insertions(+)
+int ixgbe_get_wake_addr(void *rx_queue, volatile void **tail_desc_addr,
+uint64_t *expected, uint64_t *mask)
+{
+volatile union ixgbe_adv_rx_desc *rxdp;
+struct ixgbe_rx_queue *rxq = rx_queue;
+uint16_t desc;
+
+desc = rxq->rx_tail;
+rxdp = &rxq->rx_ring[desc];
+/* watch for changes in status bit */
+*tail_desc_addr = &rxdp->wb.upper.status_error;
+
+/*
+ * we expect the DD bit to be set to 1 if this descriptor was already
+ * written to.
+ */
+*expected = rte_cpu_to_le_32(IXGBE_RXDADV_STAT_DD);
+*mask = rte_cpu_to_le_32(IXGBE_RXDADV_STAT_DD);
+
Seems have one issue about the byte endian:
Like for BIG endian:
*expected = rte_bswap32(IXGBE_RXDADV_STAT_DD)
!=
*expected = rte_bswap64(IXGBE_RXDADV_STAT_DD)
And in API 'rte_power_monitor', use uint64_t type to access the wake up
data:
static inline void rte_power_monitor(const volatile void *p,
const uint64_t expected_value, const uint64_t value_mask,
const uint64_t tsc_timestamp)
{
if (value_mask) {
const uint64_t cur_value = *(const volatile uint64_t *)p;
const uint64_t masked = cur_value & value_mask;
/* if the masked value is already matching, abort */
if (masked == expected_value)
return;
}
So that we need the wake up address type like 16/32/64b ?
Endian differences strike again! You're right of course.
I suspect casting everything to CPU endinanness would fix it, would it not?
--
2.17.1
--
Thanks,
Anatoly
