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authorLinus Torvalds <torvalds@linux-foundation.org>2020-08-04 05:08:51 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2020-08-04 05:08:51 +0200
commitb171373902b06d1b5a775de74178bf1527fee6cc (patch)
tree57f28f0d401457437dcd4945f15e10d13832b24f /drivers/spi/spi-geni-qcom.c
parentMerge tag 'regulator-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/b... (diff)
parentMerge remote-tracking branch 'spi/for-5.9' into spi-next (diff)
downloadlinux-b171373902b06d1b5a775de74178bf1527fee6cc.tar.xz
linux-b171373902b06d1b5a775de74178bf1527fee6cc.zip
Merge tag 'spi-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown: "A fairly quiet release for SPI, nothing really going on in the core although there's been quite a bit of driver related activity. This includes the addition of some shared code in drivers/memory for the Renesas RPC-IF which is used by a newly added SPI driver, the memory subsystem doesn't seem to have a fixed maintainer at the minute and this seemed like the most sensible way to get that hardware supported. - Quite a few cleanups and optimizations for the Altera, Qualcomm GENI, sun6i and lantiq drivers. - Several more GPIO descriptor conversions. - Move the Cadence QuadSPI driver from drivers/mtd to drivers/spi. - New support for Mediatek MT8192 and Renesas RPC-IF, R8A7742 and R8A774e1" * tag 'spi-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (119 commits) dt-bindings: lpspi: New property in document DT bindings for LPSPI spi: lpspi: fix using CS discontinuously on i.MX8DXLEVK spi: lpspi: remove unused fsl_lpspi->chipselect spi: lpspi: Fix kernel warning dump when probe fail after calling spi_register spi: rockchip: Fix error in SPI slave pio read spi: rockchip: Support 64-location deep FIFOs spi: rockchip: Config spi rx dma burst size depend on xfer length spi: spi-topcliff-pch: drop call to wakeup-disable spi: spidev: Align buffers for DMA spi: correct kernel-doc inconsistency spi: sun4i: update max transfer size reported spi: imx: enable runtime pm support spi: update bindings for MT8192 SoC spi: mediatek: add spi support for mt8192 IC spi: Add bindings for Lightning Mountain SoC spi: lantiq: Add support to Lightning Mountain SoC spi: lantiq: Move interrupt configuration to SoC specific data structure spi: lantiq: Add fifo size bit mask in SoC specific data structure spi: lantiq: Add support to acknowledge interrupt spi: lantiq: Move interrupt control register offesets to SoC specific data structure ...
Diffstat (limited to 'drivers/spi/spi-geni-qcom.c')
-rw-r--r--drivers/spi/spi-geni-qcom.c179
1 files changed, 112 insertions, 67 deletions
diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c
index 7a88cc036004..80cea5cd3612 100644
--- a/drivers/spi/spi-geni-qcom.c
+++ b/drivers/spi/spi-geni-qcom.c
@@ -52,7 +52,6 @@
/* M_CMD OP codes for SPI */
#define SPI_TX_ONLY 1
#define SPI_RX_ONLY 2
-#define SPI_FULL_DUPLEX 3
#define SPI_TX_RX 7
#define SPI_CS_ASSERT 8
#define SPI_CS_DEASSERT 9
@@ -64,13 +63,6 @@
#define TIMESTAMP_AFTER BIT(3)
#define POST_CMD_DELAY BIT(4)
-enum spi_m_cmd_opcode {
- CMD_NONE,
- CMD_XFER,
- CMD_CS,
- CMD_CANCEL,
-};
-
struct spi_geni_master {
struct geni_se se;
struct device *dev;
@@ -84,11 +76,13 @@ struct spi_geni_master {
unsigned int tx_rem_bytes;
unsigned int rx_rem_bytes;
const struct spi_transfer *cur_xfer;
- struct completion xfer_done;
+ struct completion cs_done;
+ struct completion cancel_done;
+ struct completion abort_done;
unsigned int oversampling;
spinlock_t lock;
- enum spi_m_cmd_opcode cur_mcmd;
int irq;
+ bool cs_flag;
};
static int get_spi_clk_cfg(unsigned int speed_hz,
@@ -127,24 +121,26 @@ static void handle_fifo_timeout(struct spi_master *spi,
struct spi_message *msg)
{
struct spi_geni_master *mas = spi_master_get_devdata(spi);
- unsigned long time_left, flags;
+ unsigned long time_left;
struct geni_se *se = &mas->se;
- spin_lock_irqsave(&mas->lock, flags);
- reinit_completion(&mas->xfer_done);
- mas->cur_mcmd = CMD_CANCEL;
- geni_se_cancel_m_cmd(se);
+ spin_lock_irq(&mas->lock);
+ reinit_completion(&mas->cancel_done);
writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
- spin_unlock_irqrestore(&mas->lock, flags);
- time_left = wait_for_completion_timeout(&mas->xfer_done, HZ);
+ mas->cur_xfer = NULL;
+ geni_se_cancel_m_cmd(se);
+ spin_unlock_irq(&mas->lock);
+
+ time_left = wait_for_completion_timeout(&mas->cancel_done, HZ);
if (time_left)
return;
- spin_lock_irqsave(&mas->lock, flags);
- reinit_completion(&mas->xfer_done);
+ spin_lock_irq(&mas->lock);
+ reinit_completion(&mas->abort_done);
geni_se_abort_m_cmd(se);
- spin_unlock_irqrestore(&mas->lock, flags);
- time_left = wait_for_completion_timeout(&mas->xfer_done, HZ);
+ spin_unlock_irq(&mas->lock);
+
+ time_left = wait_for_completion_timeout(&mas->abort_done, HZ);
if (!time_left)
dev_err(mas->dev, "Failed to cancel/abort m_cmd\n");
}
@@ -156,18 +152,24 @@ static void spi_geni_set_cs(struct spi_device *slv, bool set_flag)
struct geni_se *se = &mas->se;
unsigned long time_left;
- reinit_completion(&mas->xfer_done);
- pm_runtime_get_sync(mas->dev);
if (!(slv->mode & SPI_CS_HIGH))
set_flag = !set_flag;
- mas->cur_mcmd = CMD_CS;
+ if (set_flag == mas->cs_flag)
+ return;
+
+ mas->cs_flag = set_flag;
+
+ pm_runtime_get_sync(mas->dev);
+ spin_lock_irq(&mas->lock);
+ reinit_completion(&mas->cs_done);
if (set_flag)
geni_se_setup_m_cmd(se, SPI_CS_ASSERT, 0);
else
geni_se_setup_m_cmd(se, SPI_CS_DEASSERT, 0);
+ spin_unlock_irq(&mas->lock);
- time_left = wait_for_completion_timeout(&mas->xfer_done, HZ);
+ time_left = wait_for_completion_timeout(&mas->cs_done, HZ);
if (!time_left)
handle_fifo_timeout(spi, NULL);
@@ -306,7 +308,7 @@ static int spi_geni_init(struct spi_geni_master *mas)
* Hardware programming guide suggests to configure
* RX FIFO RFR level to fifo_depth-2.
*/
- geni_se_init(se, 0x0, mas->tx_fifo_depth - 2);
+ geni_se_init(se, mas->tx_fifo_depth / 2, mas->tx_fifo_depth - 2);
/* Transmit an entire FIFO worth of data per IRQ */
mas->tx_wm = 1;
ver = geni_se_get_qup_hw_version(se);
@@ -333,6 +335,21 @@ static void setup_fifo_xfer(struct spi_transfer *xfer,
struct geni_se *se = &mas->se;
int ret;
+ /*
+ * Ensure that our interrupt handler isn't still running from some
+ * prior command before we start messing with the hardware behind
+ * its back. We don't need to _keep_ the lock here since we're only
+ * worried about racing with out interrupt handler. The SPI core
+ * already handles making sure that we're not trying to do two
+ * transfers at once or setting a chip select and doing a transfer
+ * concurrently.
+ *
+ * NOTE: we actually _can't_ hold the lock here because possibly we
+ * might call clk_set_rate() which needs to be able to sleep.
+ */
+ spin_lock_irq(&mas->lock);
+ spin_unlock_irq(&mas->lock);
+
spi_tx_cfg = readl(se->base + SE_SPI_TRANS_CFG);
if (xfer->bits_per_word != mas->cur_bits_per_word) {
spi_setup_word_len(mas, mode, xfer->bits_per_word);
@@ -346,12 +363,6 @@ static void setup_fifo_xfer(struct spi_transfer *xfer,
mas->tx_rem_bytes = 0;
mas->rx_rem_bytes = 0;
- if (xfer->tx_buf && xfer->rx_buf)
- m_cmd = SPI_FULL_DUPLEX;
- else if (xfer->tx_buf)
- m_cmd = SPI_TX_ONLY;
- else if (xfer->rx_buf)
- m_cmd = SPI_RX_ONLY;
spi_tx_cfg &= ~CS_TOGGLE;
@@ -362,17 +373,24 @@ static void setup_fifo_xfer(struct spi_transfer *xfer,
len &= TRANS_LEN_MSK;
mas->cur_xfer = xfer;
- if (m_cmd & SPI_TX_ONLY) {
+ if (xfer->tx_buf) {
+ m_cmd |= SPI_TX_ONLY;
mas->tx_rem_bytes = xfer->len;
writel(len, se->base + SE_SPI_TX_TRANS_LEN);
}
- if (m_cmd & SPI_RX_ONLY) {
+ if (xfer->rx_buf) {
+ m_cmd |= SPI_RX_ONLY;
writel(len, se->base + SE_SPI_RX_TRANS_LEN);
mas->rx_rem_bytes = xfer->len;
}
writel(spi_tx_cfg, se->base + SE_SPI_TRANS_CFG);
- mas->cur_mcmd = CMD_XFER;
+
+ /*
+ * Lock around right before we start the transfer since our
+ * interrupt could come in at any time now.
+ */
+ spin_lock_irq(&mas->lock);
geni_se_setup_m_cmd(se, m_cmd, FRAGMENTATION);
/*
@@ -382,6 +400,7 @@ static void setup_fifo_xfer(struct spi_transfer *xfer,
*/
if (m_cmd & SPI_TX_ONLY)
writel(mas->tx_wm, se->base + SE_GENI_TX_WATERMARK_REG);
+ spin_unlock_irq(&mas->lock);
}
static int spi_geni_transfer_one(struct spi_master *spi,
@@ -483,13 +502,17 @@ static irqreturn_t geni_spi_isr(int irq, void *data)
struct spi_geni_master *mas = spi_master_get_devdata(spi);
struct geni_se *se = &mas->se;
u32 m_irq;
- unsigned long flags;
- if (mas->cur_mcmd == CMD_NONE)
+ m_irq = readl(se->base + SE_GENI_M_IRQ_STATUS);
+ if (!m_irq)
return IRQ_NONE;
- spin_lock_irqsave(&mas->lock, flags);
- m_irq = readl(se->base + SE_GENI_M_IRQ_STATUS);
+ if (m_irq & (M_CMD_OVERRUN_EN | M_ILLEGAL_CMD_EN | M_CMD_FAILURE_EN |
+ M_RX_FIFO_RD_ERR_EN | M_RX_FIFO_WR_ERR_EN |
+ M_TX_FIFO_RD_ERR_EN | M_TX_FIFO_WR_ERR_EN))
+ dev_warn(mas->dev, "Unexpected IRQ err status %#010x\n", m_irq);
+
+ spin_lock(&mas->lock);
if ((m_irq & M_RX_FIFO_WATERMARK_EN) || (m_irq & M_RX_FIFO_LAST_EN))
geni_spi_handle_rx(mas);
@@ -498,39 +521,57 @@ static irqreturn_t geni_spi_isr(int irq, void *data)
geni_spi_handle_tx(mas);
if (m_irq & M_CMD_DONE_EN) {
- if (mas->cur_mcmd == CMD_XFER)
+ if (mas->cur_xfer) {
spi_finalize_current_transfer(spi);
- else if (mas->cur_mcmd == CMD_CS)
- complete(&mas->xfer_done);
- mas->cur_mcmd = CMD_NONE;
- /*
- * If this happens, then a CMD_DONE came before all the Tx
- * buffer bytes were sent out. This is unusual, log this
- * condition and disable the WM interrupt to prevent the
- * system from stalling due an interrupt storm.
- * If this happens when all Rx bytes haven't been received, log
- * the condition.
- * The only known time this can happen is if bits_per_word != 8
- * and some registers that expect xfer lengths in num spi_words
- * weren't written correctly.
- */
- if (mas->tx_rem_bytes) {
- writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
- dev_err(mas->dev, "Premature done. tx_rem = %d bpw%d\n",
- mas->tx_rem_bytes, mas->cur_bits_per_word);
+ mas->cur_xfer = NULL;
+ /*
+ * If this happens, then a CMD_DONE came before all the
+ * Tx buffer bytes were sent out. This is unusual, log
+ * this condition and disable the WM interrupt to
+ * prevent the system from stalling due an interrupt
+ * storm.
+ *
+ * If this happens when all Rx bytes haven't been
+ * received, log the condition. The only known time
+ * this can happen is if bits_per_word != 8 and some
+ * registers that expect xfer lengths in num spi_words
+ * weren't written correctly.
+ */
+ if (mas->tx_rem_bytes) {
+ writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
+ dev_err(mas->dev, "Premature done. tx_rem = %d bpw%d\n",
+ mas->tx_rem_bytes, mas->cur_bits_per_word);
+ }
+ if (mas->rx_rem_bytes)
+ dev_err(mas->dev, "Premature done. rx_rem = %d bpw%d\n",
+ mas->rx_rem_bytes, mas->cur_bits_per_word);
+ } else {
+ complete(&mas->cs_done);
}
- if (mas->rx_rem_bytes)
- dev_err(mas->dev, "Premature done. rx_rem = %d bpw%d\n",
- mas->rx_rem_bytes, mas->cur_bits_per_word);
}
- if ((m_irq & M_CMD_CANCEL_EN) || (m_irq & M_CMD_ABORT_EN)) {
- mas->cur_mcmd = CMD_NONE;
- complete(&mas->xfer_done);
- }
+ if (m_irq & M_CMD_CANCEL_EN)
+ complete(&mas->cancel_done);
+ if (m_irq & M_CMD_ABORT_EN)
+ complete(&mas->abort_done);
+ /*
+ * It's safe or a good idea to Ack all of our our interrupts at the
+ * end of the function. Specifically:
+ * - M_CMD_DONE_EN / M_RX_FIFO_LAST_EN: Edge triggered interrupts and
+ * clearing Acks. Clearing at the end relies on nobody else having
+ * started a new transfer yet or else we could be clearing _their_
+ * done bit, but everyone grabs the spinlock before starting a new
+ * transfer.
+ * - M_RX_FIFO_WATERMARK_EN / M_TX_FIFO_WATERMARK_EN: These appear
+ * to be "latched level" interrupts so it's important to clear them
+ * _after_ you've handled the condition and always safe to do so
+ * since they'll re-assert if they're still happening.
+ */
writel(m_irq, se->base + SE_GENI_M_IRQ_CLEAR);
- spin_unlock_irqrestore(&mas->lock, flags);
+
+ spin_unlock(&mas->lock);
+
return IRQ_HANDLED;
}
@@ -591,8 +632,12 @@ static int spi_geni_probe(struct platform_device *pdev)
spi->handle_err = handle_fifo_timeout;
spi->set_cs = spi_geni_set_cs;
- init_completion(&mas->xfer_done);
+ init_completion(&mas->cs_done);
+ init_completion(&mas->cancel_done);
+ init_completion(&mas->abort_done);
spin_lock_init(&mas->lock);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_set_autosuspend_delay(&pdev->dev, 250);
pm_runtime_enable(dev);
ret = geni_icc_get(&mas->se, NULL);