// SPDX-License-Identifier: GPL-2.0
/* Marvell Octeon EP (EndPoint) Ethernet Driver
*
* Copyright (C) 2020 Marvell.
*
*/
#include <linux/pci.h>
#include <linux/etherdevice.h>
#include <linux/vmalloc.h>
#include "octep_config.h"
#include "octep_main.h"
/* Reset various index of Tx queue data structure. */
static void octep_iq_reset_indices(struct octep_iq *iq)
{
iq->fill_cnt = 0;
iq->host_write_index = 0;
iq->octep_read_index = 0;
iq->flush_index = 0;
iq->pkts_processed = 0;
iq->pkt_in_done = 0;
}
/**
* octep_iq_process_completions() - Process Tx queue completions.
*
* @iq: Octeon Tx queue data structure.
* @budget: max number of completions to be processed in one invocation.
*/
int octep_iq_process_completions(struct octep_iq *iq, u16 budget)
{
u32 compl_pkts, compl_bytes, compl_sg;
struct octep_device *oct = iq->octep_dev;
struct octep_tx_buffer *tx_buffer;
struct skb_shared_info *shinfo;
u32 fi = iq->flush_index;
struct sk_buff *skb;
u8 frags, i;
compl_pkts = 0;
compl_sg = 0;
compl_bytes = 0;
iq->octep_read_index = oct->hw_ops.update_iq_read_idx(iq);
while (likely(budget && (fi != iq->octep_read_index))) {
tx_buffer = iq->buff_info + fi;
skb = tx_buffer->skb;
fi++;
if (unlikely(fi == iq->max_count))
fi = 0;
compl_bytes += skb->len;
compl_pkts++;
budget--;
if (!tx_buffer->gather) {
dma_unmap_single(iq->dev, tx_buffer->dma,
tx_buffer->skb->len, DMA_TO_DEVICE);
dev_kfree_skb_any(skb);
continue;
}
/* Scatter/Gather */
shinfo = skb_shinfo(skb);
frags = shinfo->nr_frags;
compl_sg++;
dma_unmap_single(iq->dev, tx_buffer->sglist[0].dma_ptr[0],
tx_buffer->sglist[0].len[3], DMA_TO_DEVICE);
i = 1; /* entry 0 is main skb, unmapped above */
while (frags--) {
dma_unmap_page(iq->dev, tx_buffer->sglist[i >> 2].dma_ptr[i & 3],
tx_buffer->sglist[i >> 2].len[3 - (i & 3)], DMA_TO_DEVICE);
i++;
}
dev_kfree_skb_any(skb);
}
iq->pkts_processed += compl_pkts;
iq->stats.instr_completed += compl_pkts;
iq->stats.bytes_sent += compl_bytes;
iq->stats.sgentry_sent += compl_sg;
iq->flush_index = fi;
netdev_tx_completed_queue(iq->netdev_q, compl_pkts, compl_bytes);
if (unlikely(__netif_subqueue_stopped(iq->netdev, iq->q_no)) &&
(IQ_INSTR_SPACE(iq) >
OCTEP_WAKE_QUEUE_THRESHOLD))
netif_wake_subqueue(iq->netdev, iq->q_no);
return !budget;
}
/**
* octep_iq_free_pending() - Free Tx buffers for pending completions.
*
* @iq: Octeon Tx queue data structure.
*/
static void octep_iq_free_pending(struct octep_iq *iq)
{
struct octep_tx_buffer *tx_buffer;
struct skb_shared_info *shinfo;
u32 fi = iq->flush_index;
struct sk_buff *skb;
u8 frags, i;
while (fi != iq->host_write_index) {
tx_buffer = iq->buff_info + fi;
skb = tx_buffer->skb;
fi++;
if (unlikely(fi == iq->max_count))
fi = 0;
if (!tx_buffer->gather) {
dma_unmap_single(iq->dev, tx_buffer->dma,
tx_buffer->skb->len, DMA_TO_DEVICE);
dev_kfree_skb_any(skb);
continue;
}
/* Scatter/Gather */
shinfo = skb_shinfo(skb);
frags = shinfo->nr_frags;
dma_unmap_single(iq->dev,
tx_buffer->sglist[0].dma_ptr[0],
tx_buffer->sglist[0].len[3],
DMA_TO_DEVICE);
i = 1; /* entry 0 is main skb, unmapped above */
while (frags--) {
dma_unmap_page(iq->dev, tx_buffer->sglist[i >> 2].dma_ptr[i & 3],
tx_buffer->sglist[i >> 2].len[3 - (i & 3)], DMA_TO_DEVICE);
i++;
}
dev_kfree_skb_any(skb);
}
iq->flush_index = fi;
netdev_tx_reset_queue(netdev_get_tx_queue(iq->netdev, iq->q_no));
}
/**
* octep_clean_iqs() - Clean Tx queues to shutdown the device.
*
* @oct: Octeon device private data structure.
*
* Free the buffers in Tx queue descriptors pending completion and
* reset queue indices
*/
void octep_clean_iqs(struct octep_device *oct)
{
int i;
for (i = 0; i < oct->num_iqs; i++) {
octep_iq_free_pending(oct->iq[i]);
octep_iq_reset_indices(oct->iq[i]);
}
}
/**
* octep_setup_iq() - Setup a Tx queue.
*
* @oct: Octeon device private data structure.
* @q_no: Tx queue number to be setup.
*
* Allocate resources for a Tx queue.
*/
static int octep_setup_iq(struct octep_device *oct, int q_no)
{
u32 desc_ring_size, buff_info_size, sglist_size;
struct octep_iq *iq;
int i;
iq = vzalloc(sizeof(*iq));
if (!iq)
goto iq_alloc_err;
oct->iq[q_no] = iq;
iq->octep_dev = oct;
iq->netdev = oct->netdev;
iq->dev = &oct->pdev->dev;
iq->q_no = q_no;
iq->max_count = CFG_GET_IQ_NUM_DESC(oct->conf);
iq->ring_size_mask = iq->max_count - 1;
iq->fill_threshold = CFG_GET_IQ_DB_MIN(oct->conf);
iq->netdev_q = netdev_get_tx_queue(iq->netdev, q_no);
/* Allocate memory for hardware queue descriptors */
desc_ring_size = OCTEP_IQ_DESC_SIZE * CFG_GET_IQ_NUM_DESC(oct->conf);
iq->desc_ring = dma_alloc_coherent(iq->dev, desc_ring_size,
&iq->desc_ring_dma, GFP_KERNEL);
if (unlikely(!iq->desc_ring)) {
dev_err(iq->dev,
"Failed to allocate DMA memory for IQ-%d\n", q_no);
goto desc_dma_alloc_err;
}
/* Allocate memory for hardware SGLIST descriptors */
sglist_size = OCTEP_SGLIST_SIZE_PER_PKT *
CFG_GET_IQ_NUM_DESC(oct->conf);
iq->sglist = dma_alloc_coherent(iq->dev, sglist_size,
&iq->sglist_dma, GFP_KERNEL);
if (unlikely(!iq->sglist)) {
dev_err(iq->dev,
"Failed to allocate DMA memory for IQ-%d SGLIST\n",
q_no);
goto sglist_alloc_err;
}
/* allocate memory to manage Tx packets pending completion */
buff_info_size = OCTEP_IQ_TXBUFF_INFO_SIZE * iq->max_count;
iq->buff_info = vzalloc(buff_info_size);
if (!iq->buff_info) {
dev_err(iq->dev,
"Failed to allocate buff info for IQ-%d\n", q_no);
goto buff_info_err;
}
/* Setup sglist addresses in tx_buffer entries */
for (i = 0; i < CFG_GET_IQ_NUM_DESC(oct->conf); i++) {
struct octep_tx_buffer *tx_buffer;
tx_buffer = &iq->buff_info[i];
tx_buffer->sglist =
&iq->sglist[i * OCTEP_SGLIST_ENTRIES_PER_PKT];
tx_buffer->sglist_dma =
iq->sglist_dma + (i * OCTEP_SGLIST_SIZE_PER_PKT);
}
octep_iq_reset_indices(iq);
oct->hw_ops.setup_iq_regs(oct, q_no);
oct->num_iqs++;
return 0;
buff_info_err:
dma_free_coherent(iq->dev, sglist_size, iq->sglist, iq->sglist_dma);
sglist_alloc_err:
dma_free_coherent(iq->dev, desc_ring_size,
iq->desc_ring, iq->desc_ring_dma);
desc_dma_alloc_err:
vfree(iq);
oct->iq[q_no] = NULL;
iq_alloc_err:
return -1;
}
/**
* octep_free_iq() - Free Tx queue resources.
*
* @iq: Octeon Tx queue data structure.
*
* Free all the resources allocated for a Tx queue.
*/
static void octep_free_iq(struct octep_iq *iq)
{
struct octep_device *oct = iq->octep_dev;
u64 desc_ring_size, sglist_size;
int q_no = iq->q_no;
desc_ring_size = OCTEP_IQ_DESC_SIZE * CFG_GET_IQ_NUM_DESC(oct->conf);
vfree(iq->buff_info);
if (iq->desc_ring)
dma_free_coherent(iq->dev, desc_ring_size,
iq->desc_ring, iq->desc_ring_dma);
sglist_size = OCTEP_SGLIST_SIZE_PER_PKT *
CFG_GET_IQ_NUM_DESC(oct->conf);
if (iq->sglist)
dma_free_coherent(iq->dev, sglist_size,
iq->sglist, iq->sglist_dma);
vfree(iq);
oct->iq[q_no] = NULL;
oct->num_iqs--;
}
/**
* octep_setup_iqs() - setup resources for all Tx queues.
*
* @oct: Octeon device private data structure.
*/
int octep_setup_iqs(struct octep_device *oct)
{
int i;
oct->num_iqs = 0;
for (i = 0; i < CFG_GET_PORTS_ACTIVE_IO_RINGS(oct->conf); i++) {
if (octep_setup_iq(oct, i)) {
dev_err(&oct->pdev->dev,
"Failed to setup IQ(TxQ)-%d.\n", i);
goto iq_setup_err;
}
dev_dbg(&oct->pdev->dev, "Successfully setup IQ(TxQ)-%d.\n", i);
}
return 0;
iq_setup_err:
while (i) {
i--;
octep_free_iq(oct->iq[i]);
}
return -1;
}
/**
* octep_free_iqs() - Free resources of all Tx queues.
*
* @oct: Octeon device private data structure.
*/
void octep_free_iqs(struct octep_device *oct)
{
int i;
for (i = 0; i < CFG_GET_PORTS_ACTIVE_IO_RINGS(oct->conf); i++) {
octep_free_iq(oct->iq[i]);
dev_dbg(&oct->pdev->dev,
"Successfully destroyed IQ(TxQ)-%d.\n", i);
}
oct->num_iqs = 0;
}