u-boot/drivers/usb/mtu3/mtu3_qmu.c
Chunfeng Yun 044d7003a7 usb: mtu3: flush cache for next GPD
When flush cache of the current GPD and resume QMU, the controller
will try to access the next GPD after processing the current one,
if not flush the next GPD, the controller may get wrong GPD status.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
2021-03-10 11:48:09 +01:00

508 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* mtu3_qmu.c - Queue Management Unit driver for device controller
*
* Copyright (C) 2016 MediaTek Inc.
*
* Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
*/
/*
* Queue Management Unit (QMU) is designed to unload SW effort
* to serve DMA interrupts.
* By preparing General Purpose Descriptor (GPD) and Buffer Descriptor (BD),
* SW links data buffers and triggers QMU to send / receive data to
* host / from device at a time.
* And now only GPD is supported.
*
* For more detailed information, please refer to QMU Programming Guide
*/
#include <asm/cache.h>
#include <cpu_func.h>
#include <linux/iopoll.h>
#include <linux/types.h>
#include "mtu3.h"
#define QMU_CHECKSUM_LEN 16
#define GPD_FLAGS_HWO BIT(0)
#define GPD_FLAGS_BDP BIT(1)
#define GPD_FLAGS_BPS BIT(2)
#define GPD_FLAGS_IOC BIT(7)
#define GPD_EXT_FLAG_ZLP BIT(5)
#define DCACHELINE_SIZE CONFIG_SYS_CACHELINE_SIZE
void mtu3_flush_cache(uintptr_t addr, u32 len)
{
WARN_ON(!(void *)addr || len == 0);
flush_dcache_range(addr & ~(DCACHELINE_SIZE - 1),
ALIGN(addr + len, DCACHELINE_SIZE));
}
void mtu3_inval_cache(uintptr_t addr, u32 len)
{
WARN_ON(!(void *)addr || len == 0);
invalidate_dcache_range(addr & ~(DCACHELINE_SIZE - 1),
ALIGN(addr + len, DCACHELINE_SIZE));
}
static struct qmu_gpd *gpd_dma_to_virt(struct mtu3_gpd_ring *ring,
dma_addr_t dma_addr)
{
dma_addr_t dma_base = ring->dma;
struct qmu_gpd *gpd_head = ring->start;
u32 offset = (dma_addr - dma_base) / sizeof(*gpd_head);
if (offset >= MAX_GPD_NUM)
return NULL;
return gpd_head + offset;
}
static dma_addr_t gpd_virt_to_dma(struct mtu3_gpd_ring *ring,
struct qmu_gpd *gpd)
{
dma_addr_t dma_base = ring->dma;
struct qmu_gpd *gpd_head = ring->start;
u32 offset;
offset = gpd - gpd_head;
if (offset >= MAX_GPD_NUM)
return 0;
return dma_base + (offset * sizeof(*gpd));
}
static void gpd_ring_init(struct mtu3_gpd_ring *ring, struct qmu_gpd *gpd)
{
ring->start = gpd;
ring->enqueue = gpd;
ring->dequeue = gpd;
ring->end = gpd + MAX_GPD_NUM - 1;
}
static void reset_gpd_list(struct mtu3_ep *mep)
{
struct mtu3_gpd_ring *ring = &mep->gpd_ring;
struct qmu_gpd *gpd = ring->start;
if (gpd) {
gpd->flag &= ~GPD_FLAGS_HWO;
gpd_ring_init(ring, gpd);
mtu3_flush_cache((uintptr_t)gpd, sizeof(*gpd));
}
}
int mtu3_gpd_ring_alloc(struct mtu3_ep *mep)
{
struct qmu_gpd *gpd;
struct mtu3_gpd_ring *ring = &mep->gpd_ring;
/* software own all gpds as default */
gpd = memalign(DCACHELINE_SIZE, QMU_GPD_RING_SIZE);
if (!gpd)
return -ENOMEM;
memset(gpd, 0, QMU_GPD_RING_SIZE);
ring->dma = (dma_addr_t)gpd;
gpd_ring_init(ring, gpd);
return 0;
}
void mtu3_gpd_ring_free(struct mtu3_ep *mep)
{
struct mtu3_gpd_ring *ring = &mep->gpd_ring;
kfree(ring->start);
memset(ring, 0, sizeof(*ring));
}
void mtu3_qmu_resume(struct mtu3_ep *mep)
{
struct mtu3 *mtu = mep->mtu;
void __iomem *mbase = mtu->mac_base;
int epnum = mep->epnum;
u32 offset;
offset = mep->is_in ? USB_QMU_TQCSR(epnum) : USB_QMU_RQCSR(epnum);
mtu3_writel(mbase, offset, QMU_Q_RESUME);
if (!(mtu3_readl(mbase, offset) & QMU_Q_ACTIVE))
mtu3_writel(mbase, offset, QMU_Q_RESUME);
}
static struct qmu_gpd *advance_enq_gpd(struct mtu3_gpd_ring *ring)
{
if (ring->enqueue < ring->end)
ring->enqueue++;
else
ring->enqueue = ring->start;
return ring->enqueue;
}
static struct qmu_gpd *advance_deq_gpd(struct mtu3_gpd_ring *ring)
{
if (ring->dequeue < ring->end)
ring->dequeue++;
else
ring->dequeue = ring->start;
return ring->dequeue;
}
/* check if a ring is emtpy */
static int gpd_ring_empty(struct mtu3_gpd_ring *ring)
{
struct qmu_gpd *enq = ring->enqueue;
struct qmu_gpd *next;
if (ring->enqueue < ring->end)
next = enq + 1;
else
next = ring->start;
/* one gpd is reserved to simplify gpd preparation */
return next == ring->dequeue;
}
int mtu3_prepare_transfer(struct mtu3_ep *mep)
{
return gpd_ring_empty(&mep->gpd_ring);
}
static int mtu3_prepare_tx_gpd(struct mtu3_ep *mep, struct mtu3_request *mreq)
{
struct qmu_gpd *enq;
struct mtu3_gpd_ring *ring = &mep->gpd_ring;
struct qmu_gpd *gpd = ring->enqueue;
struct usb_request *req = &mreq->request;
/* set all fields to zero as default value */
memset(gpd, 0, sizeof(*gpd));
gpd->buffer = cpu_to_le32((u32)req->dma);
gpd->buf_len = cpu_to_le16(req->length);
/* get the next GPD */
enq = advance_enq_gpd(ring);
dev_dbg(mep->mtu->dev, "TX-EP%d queue gpd=%p, enq=%p\n",
mep->epnum, gpd, enq);
enq->flag &= ~GPD_FLAGS_HWO;
gpd->next_gpd = cpu_to_le32((u32)gpd_virt_to_dma(ring, enq));
mtu3_flush_cache((uintptr_t)enq, sizeof(*gpd));
if (req->zero)
gpd->ext_flag |= GPD_EXT_FLAG_ZLP;
gpd->flag |= GPD_FLAGS_IOC | GPD_FLAGS_HWO;
mreq->gpd = gpd;
if (req->length)
mtu3_flush_cache((uintptr_t)req->buf, req->length);
mtu3_flush_cache((uintptr_t)gpd, sizeof(*gpd));
return 0;
}
static int mtu3_prepare_rx_gpd(struct mtu3_ep *mep, struct mtu3_request *mreq)
{
struct qmu_gpd *enq;
struct mtu3_gpd_ring *ring = &mep->gpd_ring;
struct qmu_gpd *gpd = ring->enqueue;
struct usb_request *req = &mreq->request;
/* set all fields to zero as default value */
memset(gpd, 0, sizeof(*gpd));
gpd->buffer = cpu_to_le32((u32)req->dma);
gpd->data_buf_len = cpu_to_le16(req->length);
/* get the next GPD */
enq = advance_enq_gpd(ring);
dev_dbg(mep->mtu->dev, "RX-EP%d queue gpd=%p, enq=%p\n",
mep->epnum, gpd, enq);
enq->flag &= ~GPD_FLAGS_HWO;
gpd->next_gpd = cpu_to_le32((u32)gpd_virt_to_dma(ring, enq));
mtu3_flush_cache((uintptr_t)enq, sizeof(*gpd));
gpd->flag |= GPD_FLAGS_IOC | GPD_FLAGS_HWO;
mreq->gpd = gpd;
mtu3_inval_cache((uintptr_t)req->buf, req->length);
mtu3_flush_cache((uintptr_t)gpd, sizeof(*gpd));
return 0;
}
void mtu3_insert_gpd(struct mtu3_ep *mep, struct mtu3_request *mreq)
{
if (mep->is_in)
mtu3_prepare_tx_gpd(mep, mreq);
else
mtu3_prepare_rx_gpd(mep, mreq);
}
int mtu3_qmu_start(struct mtu3_ep *mep)
{
struct mtu3 *mtu = mep->mtu;
void __iomem *mbase = mtu->mac_base;
struct mtu3_gpd_ring *ring = &mep->gpd_ring;
u8 epnum = mep->epnum;
if (mep->is_in) {
/* set QMU start address */
mtu3_writel(mbase, USB_QMU_TQSAR(epnum), ring->dma);
mtu3_setbits(mbase, MU3D_EP_TXCR0(epnum), TX_DMAREQEN);
/* send zero length packet according to ZLP flag in GPD */
mtu3_setbits(mbase, U3D_QCR1, QMU_TX_ZLP(epnum));
mtu3_writel(mbase, U3D_TQERRIESR0,
QMU_TX_LEN_ERR(epnum) | QMU_TX_CS_ERR(epnum));
if (mtu3_readl(mbase, USB_QMU_TQCSR(epnum)) & QMU_Q_ACTIVE) {
dev_warn(mtu->dev, "Tx %d Active Now!\n", epnum);
return 0;
}
mtu3_writel(mbase, USB_QMU_TQCSR(epnum), QMU_Q_START);
} else {
mtu3_writel(mbase, USB_QMU_RQSAR(epnum), ring->dma);
mtu3_setbits(mbase, MU3D_EP_RXCR0(epnum), RX_DMAREQEN);
/* don't expect ZLP */
mtu3_clrbits(mbase, U3D_QCR3, QMU_RX_ZLP(epnum));
/* move to next GPD when receive ZLP */
mtu3_setbits(mbase, U3D_QCR3, QMU_RX_COZ(epnum));
mtu3_writel(mbase, U3D_RQERRIESR0,
QMU_RX_LEN_ERR(epnum) | QMU_RX_CS_ERR(epnum));
mtu3_writel(mbase, U3D_RQERRIESR1, QMU_RX_ZLP_ERR(epnum));
if (mtu3_readl(mbase, USB_QMU_RQCSR(epnum)) & QMU_Q_ACTIVE) {
dev_warn(mtu->dev, "Rx %d Active Now!\n", epnum);
return 0;
}
mtu3_writel(mbase, USB_QMU_RQCSR(epnum), QMU_Q_START);
}
return 0;
}
/* may called in atomic context */
void mtu3_qmu_stop(struct mtu3_ep *mep)
{
struct mtu3 *mtu = mep->mtu;
void __iomem *mbase = mtu->mac_base;
int epnum = mep->epnum;
u32 value = 0;
u32 qcsr;
int ret;
qcsr = mep->is_in ? USB_QMU_TQCSR(epnum) : USB_QMU_RQCSR(epnum);
if (!(mtu3_readl(mbase, qcsr) & QMU_Q_ACTIVE)) {
dev_dbg(mtu->dev, "%s's qmu is inactive now!\n", mep->name);
return;
}
mtu3_writel(mbase, qcsr, QMU_Q_STOP);
ret = readl_poll_timeout(mbase + qcsr, value,
!(value & QMU_Q_ACTIVE), 1000);
if (ret) {
dev_err(mtu->dev, "stop %s's qmu failed\n", mep->name);
return;
}
dev_dbg(mtu->dev, "%s's qmu stop now!\n", mep->name);
}
void mtu3_qmu_flush(struct mtu3_ep *mep)
{
dev_dbg(mep->mtu->dev, "%s flush QMU %s\n", __func__,
((mep->is_in) ? "TX" : "RX"));
/*Stop QMU */
mtu3_qmu_stop(mep);
reset_gpd_list(mep);
}
/*
* NOTE: request list maybe is already empty as following case:
* queue_tx --> qmu_interrupt(clear interrupt pending, schedule tasklet)-->
* queue_tx --> process_tasklet(meanwhile, the second one is transferred,
* tasklet process both of them)-->qmu_interrupt for second one.
* To avoid upper case, put qmu_done_tx in ISR directly to process it.
*/
static void qmu_done_tx(struct mtu3 *mtu, u8 epnum)
{
struct mtu3_ep *mep = mtu->in_eps + epnum;
struct mtu3_gpd_ring *ring = &mep->gpd_ring;
void __iomem *mbase = mtu->mac_base;
struct qmu_gpd *gpd = ring->dequeue;
struct qmu_gpd *gpd_current = NULL;
struct usb_request *req = NULL;
struct mtu3_request *mreq;
dma_addr_t cur_gpd_dma;
/*transfer phy address got from QMU register to virtual address */
cur_gpd_dma = mtu3_readl(mbase, USB_QMU_TQCPR(epnum));
gpd_current = gpd_dma_to_virt(ring, cur_gpd_dma);
mtu3_inval_cache((uintptr_t)gpd, sizeof(*gpd));
dev_dbg(mtu->dev, "%s EP%d, last=%p, current=%p, enq=%p\n",
__func__, epnum, gpd, gpd_current, ring->enqueue);
while (gpd != gpd_current && !(gpd->flag & GPD_FLAGS_HWO)) {
mreq = next_request(mep);
if (!mreq || mreq->gpd != gpd) {
dev_err(mtu->dev, "no correct TX req is found\n");
break;
}
req = &mreq->request;
req->actual = le16_to_cpu(gpd->buf_len);
mtu3_req_complete(mep, req, 0);
gpd = advance_deq_gpd(ring);
mtu3_inval_cache((uintptr_t)gpd, sizeof(*gpd));
}
dev_dbg(mtu->dev, "%s EP%d, deq=%p, enq=%p, complete\n",
__func__, epnum, ring->dequeue, ring->enqueue);
}
static void qmu_done_rx(struct mtu3 *mtu, u8 epnum)
{
struct mtu3_ep *mep = mtu->out_eps + epnum;
struct mtu3_gpd_ring *ring = &mep->gpd_ring;
void __iomem *mbase = mtu->mac_base;
struct qmu_gpd *gpd = ring->dequeue;
struct qmu_gpd *gpd_current = NULL;
struct usb_request *req = NULL;
struct mtu3_request *mreq;
dma_addr_t cur_gpd_dma;
cur_gpd_dma = mtu3_readl(mbase, USB_QMU_RQCPR(epnum));
gpd_current = gpd_dma_to_virt(ring, cur_gpd_dma);
mtu3_inval_cache((uintptr_t)gpd, sizeof(*gpd));
dev_dbg(mtu->dev, "%s EP%d, last=%p, current=%p, enq=%p\n",
__func__, epnum, gpd, gpd_current, ring->enqueue);
while (gpd != gpd_current && !(gpd->flag & GPD_FLAGS_HWO)) {
mreq = next_request(mep);
if (!mreq || mreq->gpd != gpd) {
dev_err(mtu->dev, "no correct RX req is found\n");
break;
}
req = &mreq->request;
req->actual = le16_to_cpu(gpd->buf_len);
mtu3_req_complete(mep, req, 0);
gpd = advance_deq_gpd(ring);
mtu3_inval_cache((uintptr_t)gpd, sizeof(*gpd));
}
dev_dbg(mtu->dev, "%s EP%d, deq=%p, enq=%p, complete\n",
__func__, epnum, ring->dequeue, ring->enqueue);
}
static void qmu_done_isr(struct mtu3 *mtu, u32 done_status)
{
int i;
for (i = 1; i < mtu->num_eps; i++) {
if (done_status & QMU_RX_DONE_INT(i))
qmu_done_rx(mtu, i);
if (done_status & QMU_TX_DONE_INT(i))
qmu_done_tx(mtu, i);
}
}
static void qmu_exception_isr(struct mtu3 *mtu, u32 qmu_status)
{
void __iomem *mbase = mtu->mac_base;
u32 errval;
int i;
if ((qmu_status & RXQ_CSERR_INT) || (qmu_status & RXQ_LENERR_INT)) {
errval = mtu3_readl(mbase, U3D_RQERRIR0);
for (i = 1; i < mtu->num_eps; i++) {
if (errval & QMU_RX_CS_ERR(i))
dev_err(mtu->dev, "Rx %d CS error!\n", i);
if (errval & QMU_RX_LEN_ERR(i))
dev_err(mtu->dev, "RX %d Length error\n", i);
}
mtu3_writel(mbase, U3D_RQERRIR0, errval);
}
if (qmu_status & RXQ_ZLPERR_INT) {
errval = mtu3_readl(mbase, U3D_RQERRIR1);
for (i = 1; i < mtu->num_eps; i++) {
if (errval & QMU_RX_ZLP_ERR(i))
dev_dbg(mtu->dev, "RX EP%d Recv ZLP\n", i);
}
mtu3_writel(mbase, U3D_RQERRIR1, errval);
}
if ((qmu_status & TXQ_CSERR_INT) || (qmu_status & TXQ_LENERR_INT)) {
errval = mtu3_readl(mbase, U3D_TQERRIR0);
for (i = 1; i < mtu->num_eps; i++) {
if (errval & QMU_TX_CS_ERR(i))
dev_err(mtu->dev, "Tx %d checksum error!\n", i);
if (errval & QMU_TX_LEN_ERR(i))
dev_err(mtu->dev, "Tx %d zlp error!\n", i);
}
mtu3_writel(mbase, U3D_TQERRIR0, errval);
}
}
irqreturn_t mtu3_qmu_isr(struct mtu3 *mtu)
{
void __iomem *mbase = mtu->mac_base;
u32 qmu_status;
u32 qmu_done_status;
/* U3D_QISAR1 is read update */
qmu_status = mtu3_readl(mbase, U3D_QISAR1);
qmu_status &= mtu3_readl(mbase, U3D_QIER1);
qmu_done_status = mtu3_readl(mbase, U3D_QISAR0);
qmu_done_status &= mtu3_readl(mbase, U3D_QIER0);
mtu3_writel(mbase, U3D_QISAR0, qmu_done_status); /* W1C */
dev_dbg(mtu->dev, "=== QMUdone[tx=%x, rx=%x] QMUexp[%x] ===\n",
(qmu_done_status & 0xFFFF), qmu_done_status >> 16,
qmu_status);
if (qmu_done_status)
qmu_done_isr(mtu, qmu_done_status);
if (qmu_status)
qmu_exception_isr(mtu, qmu_status);
return IRQ_HANDLED;
}
void mtu3_qmu_init(struct mtu3 *mtu)
{
compiletime_assert(QMU_GPD_SIZE == 16, "QMU_GPD size SHOULD be 16B");
}
void mtu3_qmu_exit(struct mtu3 *mtu)
{
}