From: Michael Hennerich Date: Wed, 23 Apr 2008 23:32:41 +0000 (+0800) Subject: [Blackfin] arch: Prevent potential Core Hang situation X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a81501af19830ff43688781edad7e9c0cbd668af;p=linux-2.6 [Blackfin] arch: Prevent potential Core Hang situation If the new value written to the PLL_CTL or VR_CTL register is the same as the previous value, the PLL wake-up will occur immediately (PLL is already locked), but the core and system clock will be bypassed for the PLL_LOCKCNT duration. For this interval, code will execute at the CLKIN rate instead of at the expected CCLK rate. Software should guard against this condition by comparing the current value to the new value before writing the new value. Signed-off-by: Michael Hennerich Signed-off-by: Bryan Wu --- diff --git a/include/asm-blackfin/mach-bf527/cdefBF52x_base.h b/include/asm-blackfin/mach-bf527/cdefBF52x_base.h index 50e14e7da3..9dbdbec8ea 100644 --- a/include/asm-blackfin/mach-bf527/cdefBF52x_base.h +++ b/include/asm-blackfin/mach-bf527/cdefBF52x_base.h @@ -29,18 +29,71 @@ */ #ifndef _CDEF_BF52X_H +#define _CDEF_BF52X_H + +#include +#include #include "defBF52x_base.h" +/* Include core specific register pointer definitions */ +#include + /* ==== begin from cdefBF534.h ==== */ /* Clock and System Control (0xFFC00000 - 0xFFC000FF) */ #define bfin_read_PLL_CTL() bfin_read16(PLL_CTL) -#define bfin_write_PLL_CTL(val) bfin_write16(PLL_CTL, val) +/* Writing to PLL_CTL initiates a PLL relock sequence. */ +static __inline__ void bfin_write_PLL_CTL(unsigned int val) +{ + unsigned long flags, iwr0, iwr1; + + if (val == bfin_read_PLL_CTL()) + return; + + local_irq_save(flags); + /* Enable the PLL Wakeup bit in SIC IWR */ + iwr0 = bfin_read32(SIC_IWR0); + iwr1 = bfin_read32(SIC_IWR1); + /* Only allow PPL Wakeup) */ + bfin_write32(SIC_IWR0, IWR_ENABLE(0)); + bfin_write32(SIC_IWR1, 0); + + bfin_write16(PLL_CTL, val); + SSYNC(); + asm("IDLE;"); + + bfin_write32(SIC_IWR0, iwr0); + bfin_write32(SIC_IWR1, iwr1); + local_irq_restore(flags); +} #define bfin_read_PLL_DIV() bfin_read16(PLL_DIV) #define bfin_write_PLL_DIV(val) bfin_write16(PLL_DIV, val) #define bfin_read_VR_CTL() bfin_read16(VR_CTL) -#define bfin_write_VR_CTL(val) bfin_write16(VR_CTL, val) +/* Writing to VR_CTL initiates a PLL relock sequence. */ +static __inline__ void bfin_write_VR_CTL(unsigned int val) +{ + unsigned long flags, iwr0, iwr1; + + if (val == bfin_read_VR_CTL()) + return; + + local_irq_save(flags); + /* Enable the PLL Wakeup bit in SIC IWR */ + iwr0 = bfin_read32(SIC_IWR0); + iwr1 = bfin_read32(SIC_IWR1); + /* Only allow PPL Wakeup) */ + bfin_write32(SIC_IWR0, IWR_ENABLE(0)); + bfin_write32(SIC_IWR1, 0); + + bfin_write16(VR_CTL, val); + SSYNC(); + asm("IDLE;"); + + bfin_write32(SIC_IWR0, iwr0); + bfin_write32(SIC_IWR1, iwr1); + local_irq_restore(flags); +} #define bfin_read_PLL_STAT() bfin_read16(PLL_STAT) #define bfin_write_PLL_STAT(val) bfin_write16(PLL_STAT, val) #define bfin_read_PLL_LOCKCNT() bfin_read16(PLL_LOCKCNT) diff --git a/include/asm-blackfin/mach-bf533/cdefBF532.h b/include/asm-blackfin/mach-bf533/cdefBF532.h index c803e14b52..154655452d 100644 --- a/include/asm-blackfin/mach-bf533/cdefBF532.h +++ b/include/asm-blackfin/mach-bf533/cdefBF532.h @@ -43,7 +43,27 @@ /* Clock and System Control (0xFFC0 0400-0xFFC0 07FF) */ #define bfin_read_PLL_CTL() bfin_read16(PLL_CTL) -#define bfin_write_PLL_CTL(val) bfin_write16(PLL_CTL,val) +/* Writing to PLL_CTL initiates a PLL relock sequence. */ +static __inline__ void bfin_write_PLL_CTL(unsigned int val) +{ + unsigned long flags, iwr; + + if (val == bfin_read_PLL_CTL()) + return; + + local_irq_save(flags); + /* Enable the PLL Wakeup bit in SIC IWR */ + iwr = bfin_read32(SIC_IWR); + /* Only allow PPL Wakeup) */ + bfin_write32(SIC_IWR, IWR_ENABLE(0)); + + bfin_write16(PLL_CTL, val); + SSYNC(); + asm("IDLE;"); + + bfin_write32(SIC_IWR, iwr); + local_irq_restore(flags); +} #define bfin_read_PLL_STAT() bfin_read16(PLL_STAT) #define bfin_write_PLL_STAT(val) bfin_write16(PLL_STAT,val) #define bfin_read_PLL_LOCKCNT() bfin_read16(PLL_LOCKCNT) @@ -57,6 +77,10 @@ static __inline__ void bfin_write_VR_CTL(unsigned int val) { unsigned long flags, iwr; + if (val == bfin_read_VR_CTL()) + return; + + local_irq_save(flags); /* Enable the PLL Wakeup bit in SIC IWR */ iwr = bfin_read32(SIC_IWR); /* Only allow PPL Wakeup) */ @@ -64,11 +88,10 @@ static __inline__ void bfin_write_VR_CTL(unsigned int val) bfin_write16(VR_CTL, val); SSYNC(); - - local_irq_save(flags); asm("IDLE;"); - local_irq_restore(flags); + bfin_write32(SIC_IWR, iwr); + local_irq_restore(flags); } /* System Interrupt Controller (0xFFC0 0C00-0xFFC0 0FFF) */ diff --git a/include/asm-blackfin/mach-bf537/cdefBF534.h b/include/asm-blackfin/mach-bf537/cdefBF534.h index 048d26a61f..82de526f80 100644 --- a/include/asm-blackfin/mach-bf537/cdefBF534.h +++ b/include/asm-blackfin/mach-bf537/cdefBF534.h @@ -44,7 +44,27 @@ /* Clock and System Control (0xFFC00000 - 0xFFC000FF) */ #define bfin_read_PLL_CTL() bfin_read16(PLL_CTL) -#define bfin_write_PLL_CTL(val) bfin_write16(PLL_CTL,val) +/* Writing to PLL_CTL initiates a PLL relock sequence. */ +static __inline__ void bfin_write_PLL_CTL(unsigned int val) +{ + unsigned long flags, iwr; + + if (val == bfin_read_PLL_CTL()) + return; + + local_irq_save(flags); + /* Enable the PLL Wakeup bit in SIC IWR */ + iwr = bfin_read32(SIC_IWR); + /* Only allow PPL Wakeup) */ + bfin_write32(SIC_IWR, IWR_ENABLE(0)); + + bfin_write16(PLL_CTL, val); + SSYNC(); + asm("IDLE;"); + + bfin_write32(SIC_IWR, iwr); + local_irq_restore(flags); +} #define bfin_read_PLL_DIV() bfin_read16(PLL_DIV) #define bfin_write_PLL_DIV(val) bfin_write16(PLL_DIV,val) #define bfin_read_VR_CTL() bfin_read16(VR_CTL) @@ -53,6 +73,10 @@ static __inline__ void bfin_write_VR_CTL(unsigned int val) { unsigned long flags, iwr; + if (val == bfin_read_VR_CTL()) + return; + + local_irq_save(flags); /* Enable the PLL Wakeup bit in SIC IWR */ iwr = bfin_read32(SIC_IWR); /* Only allow PPL Wakeup) */ @@ -60,11 +84,10 @@ static __inline__ void bfin_write_VR_CTL(unsigned int val) bfin_write16(VR_CTL, val); SSYNC(); - - local_irq_save(flags); asm("IDLE;"); - local_irq_restore(flags); + bfin_write32(SIC_IWR, iwr); + local_irq_restore(flags); } #define bfin_read_PLL_STAT() bfin_read16(PLL_STAT) #define bfin_write_PLL_STAT(val) bfin_write16(PLL_STAT,val) diff --git a/include/asm-blackfin/mach-bf548/cdefBF54x_base.h b/include/asm-blackfin/mach-bf548/cdefBF54x_base.h index 33c6750071..57ac8cb9b1 100644 --- a/include/asm-blackfin/mach-bf548/cdefBF54x_base.h +++ b/include/asm-blackfin/mach-bf548/cdefBF54x_base.h @@ -43,7 +43,33 @@ /* PLL Registers */ #define bfin_read_PLL_CTL() bfin_read16(PLL_CTL) -#define bfin_write_PLL_CTL(val) bfin_write16(PLL_CTL, val) +/* Writing to PLL_CTL initiates a PLL relock sequence. */ +static __inline__ void bfin_write_PLL_CTL(unsigned int val) +{ + unsigned long flags, iwr0, iwr1, iwr2; + + if (val == bfin_read_PLL_CTL()) + return; + + local_irq_save(flags); + /* Enable the PLL Wakeup bit in SIC IWR */ + iwr0 = bfin_read32(SIC_IWR0); + iwr1 = bfin_read32(SIC_IWR1); + iwr2 = bfin_read32(SIC_IWR2); + /* Only allow PPL Wakeup) */ + bfin_write32(SIC_IWR0, IWR_ENABLE(0)); + bfin_write32(SIC_IWR1, 0); + bfin_write32(SIC_IWR2, 0); + + bfin_write16(PLL_CTL, val); + SSYNC(); + asm("IDLE;"); + + bfin_write32(SIC_IWR0, iwr0); + bfin_write32(SIC_IWR1, iwr1); + bfin_write32(SIC_IWR2, iwr2); + local_irq_restore(flags); +} #define bfin_read_PLL_DIV() bfin_read16(PLL_DIV) #define bfin_write_PLL_DIV(val) bfin_write16(PLL_DIV, val) #define bfin_read_VR_CTL() bfin_read16(VR_CTL) @@ -52,6 +78,10 @@ static __inline__ void bfin_write_VR_CTL(unsigned int val) { unsigned long flags, iwr0, iwr1, iwr2; + if (val == bfin_read_VR_CTL()) + return; + + local_irq_save(flags); /* Enable the PLL Wakeup bit in SIC IWR */ iwr0 = bfin_read32(SIC_IWR0); iwr1 = bfin_read32(SIC_IWR1); @@ -63,13 +93,12 @@ static __inline__ void bfin_write_VR_CTL(unsigned int val) bfin_write16(VR_CTL, val); SSYNC(); - - local_irq_save(flags); asm("IDLE;"); - local_irq_restore(flags); + bfin_write32(SIC_IWR0, iwr0); bfin_write32(SIC_IWR1, iwr1); bfin_write32(SIC_IWR2, iwr2); + local_irq_restore(flags); } #define bfin_read_PLL_STAT() bfin_read16(PLL_STAT) #define bfin_write_PLL_STAT(val) bfin_write16(PLL_STAT, val) diff --git a/include/asm-blackfin/mach-bf561/cdefBF561.h b/include/asm-blackfin/mach-bf561/cdefBF561.h index 1bc8d2f89c..b07ffccd66 100644 --- a/include/asm-blackfin/mach-bf561/cdefBF561.h +++ b/include/asm-blackfin/mach-bf561/cdefBF561.h @@ -47,7 +47,30 @@ /* Clock and System Control (0xFFC00000 - 0xFFC000FF) */ #define bfin_read_PLL_CTL() bfin_read16(PLL_CTL) -#define bfin_write_PLL_CTL(val) bfin_write16(PLL_CTL,val) +/* Writing to PLL_CTL initiates a PLL relock sequence. */ +static __inline__ void bfin_write_PLL_CTL(unsigned int val) +{ + unsigned long flags, iwr0, iwr1; + + if (val == bfin_read_PLL_CTL()) + return; + + local_irq_save(flags); + /* Enable the PLL Wakeup bit in SIC IWR */ + iwr0 = bfin_read32(SICA_IWR0); + iwr1 = bfin_read32(SICA_IWR1); + /* Only allow PPL Wakeup) */ + bfin_write32(SICA_IWR0, IWR_ENABLE(0)); + bfin_write32(SICA_IWR1, 0); + + bfin_write16(PLL_CTL, val); + SSYNC(); + asm("IDLE;"); + + bfin_write32(SICA_IWR0, iwr0); + bfin_write32(SICA_IWR1, iwr1); + local_irq_restore(flags); +} #define bfin_read_PLL_DIV() bfin_read16(PLL_DIV) #define bfin_write_PLL_DIV(val) bfin_write16(PLL_DIV,val) #define bfin_read_VR_CTL() bfin_read16(VR_CTL) @@ -56,6 +79,10 @@ static __inline__ void bfin_write_VR_CTL(unsigned int val) { unsigned long flags, iwr0, iwr1; + if (val == bfin_read_VR_CTL()) + return; + + local_irq_save(flags); /* Enable the PLL Wakeup bit in SIC IWR */ iwr0 = bfin_read32(SICA_IWR0); iwr1 = bfin_read32(SICA_IWR1); @@ -65,12 +92,11 @@ static __inline__ void bfin_write_VR_CTL(unsigned int val) bfin_write16(VR_CTL, val); SSYNC(); - - local_irq_save(flags); asm("IDLE;"); - local_irq_restore(flags); + bfin_write32(SICA_IWR0, iwr0); bfin_write32(SICA_IWR1, iwr1); + local_irq_restore(flags); } #define bfin_read_PLL_STAT() bfin_read16(PLL_STAT) #define bfin_write_PLL_STAT(val) bfin_write16(PLL_STAT,val)