diff options
| author | Arnaud Pouliquen <arnaud.pouliquen@st.com> | 2019-05-22 10:25:35 +0200 |
|---|---|---|
| committer | Jassi Brar <jaswinder.singh@linaro.org> | 2019-07-10 23:08:43 -0500 |
| commit | dba9a3dfe912dc47c9dbc9ba1f5f65adbf9aea0f (patch) | |
| tree | dd43246a01c8a1e99cf2b4c569634574dd4999dc /drivers/mailbox | |
| parent | 6fbc7275c7a9ba97877050335f290341a1fd8dbf (diff) | |
mailbox: stm32_ipcc: add spinlock to fix channels concurrent access
Add spinlock protection on IPCC register update to avoid race condition.
Without this fix, stm32_ipcc_set_bits and stm32_ipcc_clr_bits can be
called in parallel for different channels. This results in register
corruptions.
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Reviewed-by: Fabien Dessenne <fabien.dessenne@st.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Diffstat (limited to 'drivers/mailbox')
| -rw-r--r-- | drivers/mailbox/stm32-ipcc.c | 37 |
1 files changed, 27 insertions, 10 deletions
diff --git a/drivers/mailbox/stm32-ipcc.c b/drivers/mailbox/stm32-ipcc.c index f91dfb1327c7..5c2d1e1f988b 100644 --- a/drivers/mailbox/stm32-ipcc.c +++ b/drivers/mailbox/stm32-ipcc.c @@ -50,6 +50,7 @@ struct stm32_ipcc { void __iomem *reg_base; void __iomem *reg_proc; struct clk *clk; + spinlock_t lock; /* protect access to IPCC registers */ int irqs[IPCC_IRQ_NUM]; int wkp; u32 proc_id; @@ -58,14 +59,24 @@ struct stm32_ipcc { u32 xmr; }; -static inline void stm32_ipcc_set_bits(void __iomem *reg, u32 mask) +static inline void stm32_ipcc_set_bits(spinlock_t *lock, void __iomem *reg, + u32 mask) { + unsigned long flags; + + spin_lock_irqsave(lock, flags); writel_relaxed(readl_relaxed(reg) | mask, reg); + spin_unlock_irqrestore(lock, flags); } -static inline void stm32_ipcc_clr_bits(void __iomem *reg, u32 mask) +static inline void stm32_ipcc_clr_bits(spinlock_t *lock, void __iomem *reg, + u32 mask) { + unsigned long flags; + + spin_lock_irqsave(lock, flags); writel_relaxed(readl_relaxed(reg) & ~mask, reg); + spin_unlock_irqrestore(lock, flags); } static irqreturn_t stm32_ipcc_rx_irq(int irq, void *data) @@ -92,7 +103,7 @@ static irqreturn_t stm32_ipcc_rx_irq(int irq, void *data) mbox_chan_received_data(&ipcc->controller.chans[chan], NULL); - stm32_ipcc_set_bits(ipcc->reg_proc + IPCC_XSCR, + stm32_ipcc_set_bits(&ipcc->lock, ipcc->reg_proc + IPCC_XSCR, RX_BIT_CHAN(chan)); ret = IRQ_HANDLED; @@ -121,7 +132,7 @@ static irqreturn_t stm32_ipcc_tx_irq(int irq, void *data) dev_dbg(dev, "%s: chan:%d tx\n", __func__, chan); /* mask 'tx channel free' interrupt */ - stm32_ipcc_set_bits(ipcc->reg_proc + IPCC_XMR, + stm32_ipcc_set_bits(&ipcc->lock, ipcc->reg_proc + IPCC_XMR, TX_BIT_CHAN(chan)); mbox_chan_txdone(&ipcc->controller.chans[chan], 0); @@ -141,10 +152,12 @@ static int stm32_ipcc_send_data(struct mbox_chan *link, void *data) dev_dbg(ipcc->controller.dev, "%s: chan:%d\n", __func__, chan); /* set channel n occupied */ - stm32_ipcc_set_bits(ipcc->reg_proc + IPCC_XSCR, TX_BIT_CHAN(chan)); + stm32_ipcc_set_bits(&ipcc->lock, ipcc->reg_proc + IPCC_XSCR, + TX_BIT_CHAN(chan)); /* unmask 'tx channel free' interrupt */ - stm32_ipcc_clr_bits(ipcc->reg_proc + IPCC_XMR, TX_BIT_CHAN(chan)); + stm32_ipcc_clr_bits(&ipcc->lock, ipcc->reg_proc + IPCC_XMR, + TX_BIT_CHAN(chan)); return 0; } @@ -163,7 +176,8 @@ static int stm32_ipcc_startup(struct mbox_chan *link) } /* unmask 'rx channel occupied' interrupt */ - stm32_ipcc_clr_bits(ipcc->reg_proc + IPCC_XMR, RX_BIT_CHAN(chan)); + stm32_ipcc_clr_bits(&ipcc->lock, ipcc->reg_proc + IPCC_XMR, + RX_BIT_CHAN(chan)); return 0; } @@ -175,7 +189,7 @@ static void stm32_ipcc_shutdown(struct mbox_chan *link) controller); /* mask rx/tx interrupt */ - stm32_ipcc_set_bits(ipcc->reg_proc + IPCC_XMR, + stm32_ipcc_set_bits(&ipcc->lock, ipcc->reg_proc + IPCC_XMR, RX_BIT_CHAN(chan) | TX_BIT_CHAN(chan)); clk_disable_unprepare(ipcc->clk); @@ -208,6 +222,8 @@ static int stm32_ipcc_probe(struct platform_device *pdev) if (!ipcc) return -ENOMEM; + spin_lock_init(&ipcc->lock); + /* proc_id */ if (of_property_read_u32(np, "st,proc-id", &ipcc->proc_id)) { dev_err(dev, "Missing st,proc-id\n"); @@ -259,9 +275,10 @@ static int stm32_ipcc_probe(struct platform_device *pdev) } /* mask and enable rx/tx irq */ - stm32_ipcc_set_bits(ipcc->reg_proc + IPCC_XMR, + stm32_ipcc_set_bits(&ipcc->lock, ipcc->reg_proc + IPCC_XMR, RX_BIT_MASK | TX_BIT_MASK); - stm32_ipcc_set_bits(ipcc->reg_proc + IPCC_XCR, XCR_RXOIE | XCR_TXOIE); + stm32_ipcc_set_bits(&ipcc->lock, ipcc->reg_proc + IPCC_XCR, + XCR_RXOIE | XCR_TXOIE); /* wakeup */ if (of_property_read_bool(np, "wakeup-source")) { |