smsc911x.c driver and SMP
From: Antti P Miettinen <hidden>
Date: 2010-08-31 06:22:40
Subsystem:
networking drivers, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Shinya Kuribayashi [off-list ref] writes:
Hi Catalin and Antti, On 10/6/2009 3:12 PM, Antti P Miettinen wrote:quoted
Catalin Marinas [off-list ref] writes:quoted
Fixed it with this new commit (I'm not posting the patch here as it's not meant for review on this list): http://www.linux-arm.org/git?p=linux-2.6.git;a=commitdiff;h=3cc8ee538f6727d1f6773fff6d8e31bc5522bfeeJust a piece of information: with vanilla 2.6.31 boot from NFS root on my PB11MPCore hangs, with this patch applied, boot succeeds.Now I'm setting up similar dev environment by chance; Cortex-A9 MPcore, slightly old kernel (say .31 or .32), and with smsc911x.c Ethernet driver required [1]. I'm auditing the required patches right now, and very interested in above patch, but it seems that blob got lost these days :-( Do you still have the patch, and would you mind sharing it with me? [1] http://www.kmckk.co.jp/eng/kzmca9/index.html -- Shinya Kuribayashi Renesas Electronics
Hmm.. hard to remember what the patch actually contained - could it be the one below? By the way - I have a KZM board so I'd be happy to test your kernels.
diff --git a/drivers/net/smsc911x.c b/drivers/net/smsc911x.c
index 94b6d26..999e89d 100644
--- a/drivers/net/smsc911x.c
+++ b/drivers/net/smsc911x.c@@ -84,8 +84,7 @@ struct smsc911x_data { */ spinlock_t mac_lock; - /* spinlock to ensure 16-bit accesses are serialised. - * unused with a 32-bit bus */ + /* spinlock to ensure register accesses are serialised */ spinlock_t dev_lock; struct phy_device *phy_dev;
@@ -118,37 +117,33 @@ struct smsc911x_data { unsigned int hashlo; }; -/* The 16-bit access functions are significantly slower, due to the locking - * necessary. If your bus hardware can be configured to do this for you - * (in response to a single 32-bit operation from software), you should use - * the 32-bit access functions instead. */ - -static inline u32 smsc911x_reg_read(struct smsc911x_data *pdata, u32 reg) +static inline u32 __smsc911x_reg_read(struct smsc911x_data *pdata, u32 reg) { if (pdata->config.flags & SMSC911X_USE_32BIT) return readl(pdata->ioaddr + reg); - if (pdata->config.flags & SMSC911X_USE_16BIT) { - u32 data; - unsigned long flags; - - /* these two 16-bit reads must be performed consecutively, so - * must not be interrupted by our own ISR (which would start - * another read operation) */ - spin_lock_irqsave(&pdata->dev_lock, flags); - data = ((readw(pdata->ioaddr + reg) & 0xFFFF) | + if (pdata->config.flags & SMSC911X_USE_16BIT) + return ((readw(pdata->ioaddr + reg) & 0xFFFF) | ((readw(pdata->ioaddr + reg + 2) & 0xFFFF) << 16)); - spin_unlock_irqrestore(&pdata->dev_lock, flags); - - return data; - } BUG(); return 0; } -static inline void smsc911x_reg_write(struct smsc911x_data *pdata, u32 reg, - u32 val) +static inline u32 smsc911x_reg_read(struct smsc911x_data *pdata, u32 reg) +{ + u32 data; + unsigned long flags; + + spin_lock_irqsave(&pdata->dev_lock, flags); + data = __smsc911x_reg_read(pdata, reg); + spin_unlock_irqrestore(&pdata->dev_lock, flags); + + return data; +} + +static inline void __smsc911x_reg_write(struct smsc911x_data *pdata, u32 reg, + u32 val) { if (pdata->config.flags & SMSC911X_USE_32BIT) { writel(val, pdata->ioaddr + reg);
@@ -156,44 +151,54 @@ static inline void smsc911x_reg_write(struct smsc911x_data *pdata, u32 reg, } if (pdata->config.flags & SMSC911X_USE_16BIT) { - unsigned long flags; - - /* these two 16-bit writes must be performed consecutively, so - * must not be interrupted by our own ISR (which would start - * another read operation) */ - spin_lock_irqsave(&pdata->dev_lock, flags); writew(val & 0xFFFF, pdata->ioaddr + reg); writew((val >> 16) & 0xFFFF, pdata->ioaddr + reg + 2); - spin_unlock_irqrestore(&pdata->dev_lock, flags); return; } BUG(); } +static inline void smsc911x_reg_write(struct smsc911x_data *pdata, u32 reg, + u32 val) +{ + unsigned long flags; + + spin_lock_irqsave(&pdata->dev_lock, flags); + __smsc911x_reg_write(pdata, reg, val); + spin_unlock_irqrestore(&pdata->dev_lock, flags); +} + /* Writes a packet to the TX_DATA_FIFO */ static inline void smsc911x_tx_writefifo(struct smsc911x_data *pdata, unsigned int *buf, unsigned int wordcount) { + unsigned long flags; + + spin_lock_irqsave(&pdata->dev_lock, flags); + if (pdata->config.flags & SMSC911X_SWAP_FIFO) { while (wordcount--) - smsc911x_reg_write(pdata, TX_DATA_FIFO, swab32(*buf++)); - return; + __smsc911x_reg_write(pdata, TX_DATA_FIFO, + swab32(*buf++)); + goto out; } if (pdata->config.flags & SMSC911X_USE_32BIT) { writesl(pdata->ioaddr + TX_DATA_FIFO, buf, wordcount); - return; + goto out; } if (pdata->config.flags & SMSC911X_USE_16BIT) { while (wordcount--) - smsc911x_reg_write(pdata, TX_DATA_FIFO, *buf++); - return; + __smsc911x_reg_write(pdata, TX_DATA_FIFO, *buf++); + goto out; } BUG(); +out: + spin_unlock_irqrestore(&pdata->dev_lock, flags); } /* Reads a packet out of the RX_DATA_FIFO */
@@ -201,24 +206,31 @@ static inline void smsc911x_rx_readfifo(struct smsc911x_data *pdata, unsigned int *buf, unsigned int wordcount) { + unsigned long flags; + + spin_lock_irqsave(&pdata->dev_lock, flags); + if (pdata->config.flags & SMSC911X_SWAP_FIFO) { while (wordcount--) - *buf++ = swab32(smsc911x_reg_read(pdata, RX_DATA_FIFO)); - return; + *buf++ = swab32(__smsc911x_reg_read(pdata, + RX_DATA_FIFO)); + goto out; } if (pdata->config.flags & SMSC911X_USE_32BIT) { readsl(pdata->ioaddr + RX_DATA_FIFO, buf, wordcount); - return; + goto out; } if (pdata->config.flags & SMSC911X_USE_16BIT) { while (wordcount--) - *buf++ = smsc911x_reg_read(pdata, RX_DATA_FIFO); - return; + *buf++ = __smsc911x_reg_read(pdata, RX_DATA_FIFO); + goto out; } BUG(); +out: + spin_unlock_irqrestore(&pdata->dev_lock, flags); } /* waits for MAC not busy, with timeout. Only called by smsc911x_mac_read
--
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