[RFC PATCH v3.1 21/27] mmc: sdhci-uhs2: add irq() and others

From: AKASHI Takahiro
Date: Thu Nov 05 2020 - 21:29:32 EST

This is a UHS-II version of sdhci's request() operation.
It handles UHS-II related command interrupts and errors.

Signed-off-by: Ben Chuang <ben.chuang@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@xxxxxxxxxx>
---
drivers/mmc/host/sdhci-uhs2.c | 247 ++++++++++++++++++++++++++++++++++
drivers/mmc/host/sdhci-uhs2.h | 3 +
drivers/mmc/host/sdhci.c | 112 ++++++++-------
drivers/mmc/host/sdhci.h | 6 +
4 files changed, 319 insertions(+), 49 deletions(-)

diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
index 36e52553977a..d50134e912f3 100644
--- a/drivers/mmc/host/sdhci-uhs2.c
+++ b/drivers/mmc/host/sdhci-uhs2.c
@@ -11,6 +11,7 @@
*/

#include <linux/delay.h>
+#include <linux/dmaengine.h>
#include <linux/ktime.h>
#include <linux/module.h>
#include <linux/mmc/mmc.h>
@@ -670,6 +671,12 @@ static inline void sdhci_external_dma_pre_transfer(struct sdhci_host *host,
struct mmc_command *cmd)
{
}
+
+static inline struct dma_chan *sdhci_external_dma_channel(struct sdhci_host *host,
+ struct mmc_data *data)
+{
+ return NULL;
+}
#endif /* CONFIG_MMC_SDHCI_EXTERNAL_DMA */

static void sdhci_uhs2_finish_data(struct sdhci_host *host)
@@ -1051,6 +1058,246 @@ static void sdhci_uhs2_finish_command(struct sdhci_host *host)
}
}

+/*****************************************************************************\
+ * *
+ * Request done *
+ * *
+\*****************************************************************************/
+
+static bool sdhci_uhs2_request_done(struct sdhci_host *host)
+{
+ unsigned long flags;
+ struct mmc_request *mrq;
+ int i;
+
+ /* FIXME: UHS2_INITIALIZED, instead? */
+ if (!(host->mmc->flags & MMC_UHS2_SUPPORT))
+ return sdhci_request_done(host);
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ for (i = 0; i < SDHCI_MAX_MRQS; i++) {
+ mrq = host->mrqs_done[i];
+ if (mrq)
+ break;
+ }
+
+ if (!mrq) {
+ spin_unlock_irqrestore(&host->lock, flags);
+ return true;
+ }
+
+ /*
+ * Always unmap the data buffers if they were mapped by
+ * sdhci_prepare_data() whenever we finish with a request.
+ * This avoids leaking DMA mappings on error.
+ */
+ if (host->flags & SDHCI_REQ_USE_DMA) {
+ struct mmc_data *data = mrq->data;
+
+ if (host->use_external_dma && data &&
+ (mrq->cmd->error || data->error)) {
+ struct dma_chan *chan = sdhci_external_dma_channel(host, data);
+
+ host->mrqs_done[i] = NULL;
+ spin_unlock_irqrestore(&host->lock, flags);
+ dmaengine_terminate_sync(chan);
+ spin_lock_irqsave(&host->lock, flags);
+ sdhci_set_mrq_done(host, mrq);
+ }
+
+ sdhci_request_done_dma(host, mrq);
+ }
+
+ /*
+ * The controller needs a reset of internal state machines
+ * upon error conditions.
+ */
+ if (sdhci_needs_reset(host, mrq)) {
+ /*
+ * Do not finish until command and data lines are available for
+ * reset. Note there can only be one other mrq, so it cannot
+ * also be in mrqs_done, otherwise host->cmd and host->data_cmd
+ * would both be null.
+ */
+ if (host->cmd || host->data_cmd) {
+ spin_unlock_irqrestore(&host->lock, flags);
+ return true;
+ }
+
+ /* Some controllers need this kick or reset won't work here */
+ if (host->quirks & SDHCI_QUIRK_CLOCK_BEFORE_RESET)
+ /* This is to force an update */
+ host->ops->set_clock(host, host->clock);
+
+ sdhci_uhs2_reset(host, SDHCI_UHS2_SW_RESET_SD);
+ host->pending_reset = false;
+ }
+
+ host->mrqs_done[i] = NULL;
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ if (host->ops->request_done)
+ host->ops->request_done(host, mrq);
+ else
+ mmc_request_done(host->mmc, mrq);
+
+ return false;
+}
+
+static void sdhci_uhs2_complete_work(struct work_struct *work)
+{
+ struct sdhci_host *host = container_of(work, struct sdhci_host,
+ complete_work);
+
+ while (!sdhci_uhs2_request_done(host))
+ ;
+}
+
+/*****************************************************************************\
+ * *
+ * Interrupt handling *
+ * *
+\*****************************************************************************/
+
+static void __sdhci_uhs2_irq(struct sdhci_host *host, u32 uhs2mask)
+{
+ struct mmc_command *cmd = host->cmd;
+
+ DBG("*** %s got UHS2 error interrupt: 0x%08x\n",
+ mmc_hostname(host->mmc), uhs2mask);
+
+ if (uhs2mask & SDHCI_UHS2_ERR_INT_STATUS_CMD_MASK) {
+ if (!host->cmd) {
+ pr_err("%s: Got cmd interrupt 0x%08x but no cmd.\n",
+ mmc_hostname(host->mmc),
+ (unsigned int)uhs2mask);
+ sdhci_dumpregs(host);
+ return;
+ }
+ host->cmd->error = -EILSEQ;
+ if (uhs2mask & SDHCI_UHS2_ERR_INT_STATUS_RES_TIMEOUT)
+ host->cmd->error = -ETIMEDOUT;
+ }
+
+ if (uhs2mask & SDHCI_UHS2_ERR_INT_STATUS_DATA_MASK) {
+ if (!host->data) {
+ pr_err("%s: Got data interrupt 0x%08x but no data.\n",
+ mmc_hostname(host->mmc),
+ (unsigned int)uhs2mask);
+ sdhci_dumpregs(host);
+ return;
+ }
+
+ if (uhs2mask & SDHCI_UHS2_ERR_INT_STATUS_DEADLOCK_TIMEOUT) {
+ pr_err("%s: Got deadlock timeout interrupt 0x%08x\n",
+ mmc_hostname(host->mmc),
+ (unsigned int)uhs2mask);
+ host->data->error = -ETIMEDOUT;
+ } else if (uhs2mask & SDHCI_UHS2_ERR_INT_STATUS_ADMA) {
+ pr_err("%s: ADMA error = 0x %x\n",
+ mmc_hostname(host->mmc),
+ sdhci_readb(host, SDHCI_ADMA_ERROR));
+ host->data->error = -EIO;
+ } else {
+ host->data->error = -EILSEQ;
+ }
+ }
+
+ if (host->data && host->data->error)
+ sdhci_uhs2_finish_data(host);
+ else
+ sdhci_finish_mrq(host, cmd->mrq);
+}
+
+u32 sdhci_uhs2_irq(struct sdhci_host *host, u32 intmask)
+{
+ u32 mask = intmask, uhs2mask;
+
+ if (!(host->mmc->flags & MMC_UHS2_SUPPORT))
+ goto out;
+
+ /*
+ * TODO: We should mask Normal Error Interrupt Status Register
+ * in UHS-2 mode so that we don't have to care SD mode errors.
+ */
+ if (intmask & SDHCI_INT_ERROR) {
+ uhs2mask = sdhci_readl(host, SDHCI_UHS2_ERR_INT_STATUS);
+ if (!(uhs2mask & SDHCI_UHS2_ERR_INT_STATUS_MASK))
+ goto cmd_irq;
+
+ /* Clear error interrupts */
+ sdhci_writel(host, uhs2mask & SDHCI_UHS2_ERR_INT_STATUS_MASK,
+ SDHCI_UHS2_ERR_INT_STATUS);
+
+ /* Handle error interrupts */
+ __sdhci_uhs2_irq(host, uhs2mask);
+
+ /* Caller, shdci_irq(), doesn't have to care UHS-2 errors */
+ intmask &= ~SDHCI_INT_ERROR;
+ mask &= SDHCI_INT_ERROR;
+ }
+
+cmd_irq:
+ /*
+ * TODO: Cleanup
+ * INT_RESPONSE is enough instead of INT_CMD_MASK, assuming that
+ * INT_ERROR and INT_CMD_MASK won't happen at the same time.
+ */
+ if (intmask & SDHCI_INT_CMD_MASK) {
+ /* Clear command interrupt */
+ sdhci_writel(host, intmask & SDHCI_INT_CMD_MASK,
+ SDHCI_INT_STATUS);
+
+ /* Handle command interrupt */
+ if (intmask & SDHCI_INT_RESPONSE)
+ sdhci_uhs2_finish_command(host);
+
+ /* Caller, shdci_irq(), doesn't have to care UHS-2 command */
+ intmask &= ~SDHCI_INT_CMD_MASK;
+ mask &= SDHCI_INT_CMD_MASK;
+ }
+
+ /* Clear already-handled interrupts. */
+ sdhci_writel(host, mask, SDHCI_INT_STATUS);
+
+out:
+ return intmask;
+}
+EXPORT_SYMBOL_GPL(sdhci_uhs2_irq);
+
+static irqreturn_t sdhci_uhs2_thread_irq(int irq, void *dev_id)
+{
+ struct sdhci_host *host = dev_id;
+ struct mmc_command *cmd;
+ unsigned long flags;
+ u32 isr;
+
+ while (!sdhci_uhs2_request_done(host))
+ ;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ isr = host->thread_isr;
+ host->thread_isr = 0;
+
+ cmd = host->deferred_cmd;
+ if (cmd && !sdhci_uhs2_send_command_retry(host, cmd, flags))
+ sdhci_finish_mrq(host, cmd->mrq);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ if (isr & (SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE)) {
+ struct mmc_host *mmc = host->mmc;
+
+ mmc->ops->card_event(mmc);
+ mmc_detect_change(mmc, msecs_to_jiffies(200));
+ }
+
+ return IRQ_HANDLED;
+}
+
/*****************************************************************************\
* *
* Driver init/exit *
diff --git a/drivers/mmc/host/sdhci-uhs2.h b/drivers/mmc/host/sdhci-uhs2.h
index c1ff4ac1ab7a..b74af641d00e 100644
--- a/drivers/mmc/host/sdhci-uhs2.h
+++ b/drivers/mmc/host/sdhci-uhs2.h
@@ -215,5 +215,8 @@ void sdhci_uhs2_set_power(struct sdhci_host *host, unsigned char mode,
unsigned short vdd);
void sdhci_uhs2_set_timeout(struct sdhci_host *host, struct mmc_command *cmd);
void sdhci_uhs2_clear_set_irqs(struct sdhci_host *host, u32 clear, u32 set);
+void sdhci_uhs2_request(struct mmc_host *mmc, struct mmc_request *mrq);
+int sdhci_uhs2_request_atomic(struct mmc_host *mmc, struct mmc_request *mrq);
+u32 sdhci_uhs2_irq(struct sdhci_host *host, u32 intmask);

#endif /* __SDHCI_UHS2_H */
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index a9f5449bddcc..e2dfc7767bcf 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1215,11 +1215,12 @@ static int sdhci_external_dma_init(struct sdhci_host *host)
return ret;
}

-static struct dma_chan *sdhci_external_dma_channel(struct sdhci_host *host,
- struct mmc_data *data)
+struct dma_chan *sdhci_external_dma_channel(struct sdhci_host *host,
+ struct mmc_data *data)
{
return data->flags & MMC_DATA_WRITE ? host->tx_chan : host->rx_chan;
}
+EXPORT_SYMBOL_GPL(sdhci_external_dma_channel);

int sdhci_external_dma_setup(struct sdhci_host *host, struct mmc_command *cmd)
{
@@ -1466,7 +1467,7 @@ static void sdhci_set_transfer_mode(struct sdhci_host *host,
sdhci_writew(host, mode, SDHCI_TRANSFER_MODE);
}

-static bool sdhci_needs_reset(struct sdhci_host *host, struct mmc_request *mrq)
+bool sdhci_needs_reset(struct sdhci_host *host, struct mmc_request *mrq)
{
return (!(host->flags & SDHCI_DEVICE_DEAD) &&
((mrq->cmd && mrq->cmd->error) ||
@@ -1474,8 +1475,9 @@ static bool sdhci_needs_reset(struct sdhci_host *host, struct mmc_request *mrq)
(mrq->data && mrq->data->stop && mrq->data->stop->error) ||
(host->quirks & SDHCI_QUIRK_RESET_AFTER_REQUEST)));
}
+EXPORT_SYMBOL_GPL(sdhci_needs_reset);

-static void sdhci_set_mrq_done(struct sdhci_host *host, struct mmc_request *mrq)
+void sdhci_set_mrq_done(struct sdhci_host *host, struct mmc_request *mrq)
{
int i;

@@ -1495,6 +1497,7 @@ static void sdhci_set_mrq_done(struct sdhci_host *host, struct mmc_request *mrq)

WARN_ON(i >= SDHCI_MAX_MRQS);
}
+EXPORT_SYMBOL_GPL(sdhci_set_mrq_done);

void __sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq)
{
@@ -3029,7 +3032,56 @@ static const struct mmc_host_ops sdhci_ops = {
* *
\*****************************************************************************/

-static bool sdhci_request_done(struct sdhci_host *host)
+void sdhci_request_done_dma(struct sdhci_host *host, struct mmc_request *mrq)
+{
+ struct mmc_data *data = mrq->data;
+
+ if (data && data->host_cookie == COOKIE_MAPPED) {
+ if (host->bounce_buffer) {
+ /*
+ * On reads, copy the bounced data into the
+ * sglist
+ */
+ if (mmc_get_dma_dir(data) == DMA_FROM_DEVICE) {
+ unsigned int length = data->bytes_xfered;
+
+ if (length > host->bounce_buffer_size) {
+ pr_err("%s: bounce buffer is %u bytes but DMA claims to have transferred %u bytes\n",
+ mmc_hostname(host->mmc),
+ host->bounce_buffer_size,
+ data->bytes_xfered);
+ /* Cap it down and continue */
+ length = host->bounce_buffer_size;
+ }
+ dma_sync_single_for_cpu(
+ host->mmc->parent,
+ host->bounce_addr,
+ host->bounce_buffer_size,
+ DMA_FROM_DEVICE);
+ sg_copy_from_buffer(data->sg,
+ data->sg_len,
+ host->bounce_buffer,
+ length);
+ } else {
+ /* No copying, just switch ownership */
+ dma_sync_single_for_cpu(
+ host->mmc->parent,
+ host->bounce_addr,
+ host->bounce_buffer_size,
+ mmc_get_dma_dir(data));
+ }
+ } else {
+ /* Unmap the raw data */
+ dma_unmap_sg(mmc_dev(host->mmc), data->sg,
+ data->sg_len,
+ mmc_get_dma_dir(data));
+ }
+ data->host_cookie = COOKIE_UNMAPPED;
+ }
+}
+EXPORT_SYMBOL_GPL(sdhci_request_done_dma);
+
+bool sdhci_request_done(struct sdhci_host *host)
{
unsigned long flags;
struct mmc_request *mrq;
@@ -3067,48 +3119,7 @@ static bool sdhci_request_done(struct sdhci_host *host)
sdhci_set_mrq_done(host, mrq);
}

- if (data && data->host_cookie == COOKIE_MAPPED) {
- if (host->bounce_buffer) {
- /*
- * On reads, copy the bounced data into the
- * sglist
- */
- if (mmc_get_dma_dir(data) == DMA_FROM_DEVICE) {
- unsigned int length = data->bytes_xfered;
-
- if (length > host->bounce_buffer_size) {
- pr_err("%s: bounce buffer is %u bytes but DMA claims to have transferred %u bytes\n",
- mmc_hostname(host->mmc),
- host->bounce_buffer_size,
- data->bytes_xfered);
- /* Cap it down and continue */
- length = host->bounce_buffer_size;
- }
- dma_sync_single_for_cpu(
- host->mmc->parent,
- host->bounce_addr,
- host->bounce_buffer_size,
- DMA_FROM_DEVICE);
- sg_copy_from_buffer(data->sg,
- data->sg_len,
- host->bounce_buffer,
- length);
- } else {
- /* No copying, just switch ownership */
- dma_sync_single_for_cpu(
- host->mmc->parent,
- host->bounce_addr,
- host->bounce_buffer_size,
- mmc_get_dma_dir(data));
- }
- } else {
- /* Unmap the raw data */
- dma_unmap_sg(mmc_dev(host->mmc), data->sg,
- data->sg_len,
- mmc_get_dma_dir(data));
- }
- data->host_cookie = COOKIE_UNMAPPED;
- }
+ sdhci_request_done_dma(host, mrq);
}

/*
@@ -3132,8 +3143,10 @@ static bool sdhci_request_done(struct sdhci_host *host)
/* This is to force an update */
host->ops->set_clock(host, host->clock);

- /* Spec says we should do both at the same time, but Ricoh
- controllers do not like that. */
+ /*
+ * Spec says we should do both at the same time, but
+ * Ricoh controllers do not like that.
+ */
sdhci_do_reset(host, SDHCI_RESET_CMD);
sdhci_do_reset(host, SDHCI_RESET_DATA);

@@ -3151,6 +3164,7 @@ static bool sdhci_request_done(struct sdhci_host *host)

return false;
}
+EXPORT_SYMBOL_GPL(sdhci_request_done);

static void sdhci_complete_work(struct work_struct *work)
{
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 6eeb74741da3..74572b54ec47 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -845,8 +845,12 @@ void __sdhci_external_dma_prepare_data(struct sdhci_host *host,
struct mmc_command *cmd);
void sdhci_external_dma_pre_transfer(struct sdhci_host *host,
struct mmc_command *cmd);
+struct dma_chan *sdhci_external_dma_channel(struct sdhci_host *host,
+ struct mmc_data *data);
#endif
bool sdhci_manual_cmd23(struct sdhci_host *host, struct mmc_request *mrq);
+bool sdhci_needs_reset(struct sdhci_host *host, struct mmc_request *mrq);
+void sdhci_set_mrq_done(struct sdhci_host *host, struct mmc_request *mrq);
void __sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq);
void sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq);
void __sdhci_finish_data_common(struct sdhci_host *host);
@@ -878,6 +882,8 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios);
int sdhci_start_signal_voltage_switch(struct mmc_host *mmc,
struct mmc_ios *ios);
void sdhci_enable_sdio_irq(struct mmc_host *mmc, int enable);
+void sdhci_request_done_dma(struct sdhci_host *host, struct mmc_request *mrq);
+bool sdhci_request_done(struct sdhci_host *host);
void sdhci_adma_write_desc(struct sdhci_host *host, void **desc,
dma_addr_t addr, int len, unsigned int cmd);

--
2.28.0