diff options
author | David Daney <ddaney@caviumnetworks.com> | 2010-10-07 16:03:53 -0700 |
---|---|---|
committer | Ralf Baechle <ralf@linux-mips.org> | 2010-10-29 19:08:43 +0100 |
commit | c9941158fd8a539a56b0e8a4740ec1f6beb23ea3 (patch) | |
tree | 73e3868737061e1d5b0b61c182ea443e3ccd94e3 /arch/mips/cavium-octeon | |
parent | 468ffde46d429fbd291b0ef43a06afe9c837629f (diff) | |
download | linux-c9941158fd8a539a56b0e8a4740ec1f6beb23ea3.tar.bz2 |
MIPS: Octeon: Apply CN63XXP1 errata workarounds.
The CN63XXP1 needs a couple of workarounds to ensure memory is not written
in unexpected ways.
All PREF with hints in the range 0-4,6-24 are replaced with PREF 28. We
pass a flag to the assembler to cover compiler generated code, and patch
uasm for the dynamically generated code.
The write buffer threshold is reduced to 4.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Patchwork: http://patchwork.linux-mips.org/patch/1672/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/cavium-octeon')
-rw-r--r-- | arch/mips/cavium-octeon/Kconfig | 11 | ||||
-rw-r--r-- | arch/mips/cavium-octeon/setup.c | 42 |
2 files changed, 49 insertions, 4 deletions
diff --git a/arch/mips/cavium-octeon/Kconfig b/arch/mips/cavium-octeon/Kconfig index 475156b0c807..caae22858163 100644 --- a/arch/mips/cavium-octeon/Kconfig +++ b/arch/mips/cavium-octeon/Kconfig @@ -3,6 +3,17 @@ config CAVIUM_OCTEON_SPECIFIC_OPTIONS depends on CPU_CAVIUM_OCTEON default "y" +config CAVIUM_CN63XXP1 + bool "Enable CN63XXP1 errata worarounds" + depends on CAVIUM_OCTEON_SPECIFIC_OPTIONS + default "n" + help + The CN63XXP1 chip requires build time workarounds to + function reliably, select this option to enable them. These + workarounds will cause a slight decrease in performance on + non-CN63XXP1 hardware, so it is recommended to select "n" + unless it is known the workarounds are needed. + config CAVIUM_OCTEON_2ND_KERNEL bool "Build the kernel to be used as a 2nd kernel on the same chip" depends on CAVIUM_OCTEON_SPECIFIC_OPTIONS diff --git a/arch/mips/cavium-octeon/setup.c b/arch/mips/cavium-octeon/setup.c index c072b24f4853..b0c3686c96dd 100644 --- a/arch/mips/cavium-octeon/setup.c +++ b/arch/mips/cavium-octeon/setup.c @@ -356,8 +356,18 @@ void octeon_user_io_init(void) cvmmemctl.s.wbfltime = 0; /* R/W If set, do not put Istream in the L2 cache. */ cvmmemctl.s.istrnol2 = 0; - /* R/W The write buffer threshold. */ - cvmmemctl.s.wbthresh = 10; + + /* + * R/W The write buffer threshold. As per erratum Core-14752 + * for CN63XX, a sc/scd might fail if the write buffer is + * full. Lowering WBTHRESH greatly lowers the chances of the + * write buffer ever being full and triggering the erratum. + */ + if (OCTEON_IS_MODEL(OCTEON_CN63XX_PASS1_X)) + cvmmemctl.s.wbthresh = 4; + else + cvmmemctl.s.wbthresh = 10; + /* R/W If set, CVMSEG is available for loads/stores in * kernel/debug mode. */ #if CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE > 0 @@ -375,14 +385,13 @@ void octeon_user_io_init(void) * is max legal value. */ cvmmemctl.s.lmemsz = CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE; + write_c0_cvmmemctl(cvmmemctl.u64); if (smp_processor_id() == 0) pr_notice("CVMSEG size: %d cache lines (%d bytes)\n", CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE, CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE * 128); - write_c0_cvmmemctl(cvmmemctl.u64); - /* Move the performance counter interrupts to IRQ 6 */ cvmctl = read_c0_cvmctl(); cvmctl &= ~(7 << 7); @@ -758,6 +767,31 @@ EXPORT_SYMBOL(prom_putchar); void prom_free_prom_memory(void) { + if (OCTEON_IS_MODEL(OCTEON_CN63XX_PASS1_X)) { + /* Check for presence of Core-14449 fix. */ + u32 insn; + u32 *foo; + + foo = &insn; + + asm volatile("# before" : : : "memory"); + prefetch(foo); + asm volatile( + ".set push\n\t" + ".set noreorder\n\t" + "bal 1f\n\t" + "nop\n" + "1:\tlw %0,-12($31)\n\t" + ".set pop\n\t" + : "=r" (insn) : : "$31", "memory"); + + if ((insn >> 26) != 0x33) + panic("No PREF instruction at Core-14449 probe point.\n"); + + if (((insn >> 16) & 0x1f) != 28) + panic("Core-14449 WAR not in place (%04x).\n" + "Please build kernel with proper options (CONFIG_CAVIUM_CN63XXP1).\n", insn); + } #ifdef CONFIG_CAVIUM_DECODE_RSL cvmx_interrupt_rsl_enable(); |