From mboxrd@z Thu Jan 1 00:00:00 1970 From: Albert ARIBAUD Date: Thu, 16 Apr 2015 15:42:32 +0200 Subject: [U-Boot] [PATCH 1/1] ARMv7 TLB: Fixed TTBR0 and Table Descriptors to allow caching In-Reply-To: <1427214312-10855-1-git-send-email-bryan.brinsko@rockwellcollins.com> References: <1427214312-10855-1-git-send-email-bryan.brinsko@rockwellcollins.com> Message-ID: <20150416154232.738170ae@lilith> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hello Bryan, On Tue, 24 Mar 2015 11:25:12 -0500, Bryan Brinsko wrote: > The TTBR0 register and Table Descriptors of the ARMv7 TLB weren't being > properly set to allow for the configuration specified caching modes to > be active over DRAM. This commit fixes those issues. > > Signed-off-by: Bryan Brinsko > --- > arch/arm/include/asm/system.h | 37 +++++++++++++++++++++++++++++++++++++ > arch/arm/lib/cache-cp15.c | 14 ++++++++++++++ > 2 files changed, 51 insertions(+) > > diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h > index 2a5bed2..9cd2f1e 100644 > --- a/arch/arm/include/asm/system.h > +++ b/arch/arm/include/asm/system.h > @@ -196,6 +196,28 @@ static inline void set_dacr(unsigned int val) > isb(); > } > > +#ifdef CONFIG_ARMV7 > +/* Short-Descriptor Translation Table Level 1 Bits */ > +#define TTB_SECT_NS_MASK (1 << 19) > +#define TTB_SECT_NG_MASK (1 << 17) > +#define TTB_SECT_S_MASK (1 << 16) > +/* Note: TTB AP bits are set elsewhere */ > +#define TTB_SECT_TEX(x) ((x & 0x7) << 12) > +#define TTB_SECT_DOMAIN(x) ((x & 0xf) << 5) > +#define TTB_SECT_XN_MASK (1 << 4) > +#define TTB_SECT_C_MASK (1 << 3) > +#define TTB_SECT_B_MASK (1 << 2) > +#define TTB_SECT (2 << 0) > + > +/* options available for data cache on each page */ > +enum dcache_option { > + DCACHE_OFF = TTB_SECT_S_MASK | TTB_SECT_DOMAIN(0) | > + TTB_SECT_XN_MASK | TTB_SECT, > + DCACHE_WRITETHROUGH = DCACHE_OFF | TTB_SECT_C_MASK, > + DCACHE_WRITEBACK = DCACHE_WRITETHROUGH | TTB_SECT_B_MASK, > + DCACHE_WRITEALLOC = DCACHE_WRITEBACK | TTB_SECT_TEX(1), > +}; > +#else > /* options available for data cache on each page */ > enum dcache_option { > DCACHE_OFF = 0x12, > @@ -203,6 +225,7 @@ enum dcache_option { > DCACHE_WRITEBACK = 0x1e, > DCACHE_WRITEALLOC = 0x16, > }; > +#endif > > /* Size of an MMU section */ > enum { > @@ -210,6 +233,20 @@ enum { > MMU_SECTION_SIZE = 1 << MMU_SECTION_SHIFT, > }; > > +#ifdef CONFIG_ARMV7 > +/* TTBR0 bits */ > +#define TTBR0_BASE_ADDR_MASK 0xFFFFC000 > +#define TTBR0_RGN_NC (0 << 3) > +#define TTBR0_RGN_WBWA (1 << 3) > +#define TTBR0_RGN_WT (2 << 3) > +#define TTBR0_RGN_WB (3 << 3) > +/* TTBR0[6] is IRGN[0] and TTBR[0] is IRGN[1] */ > +#define TTBR0_IRGN_NC (0 << 0 | 0 << 6) > +#define TTBR0_IRGN_WBWA (0 << 0 | 1 << 6) > +#define TTBR0_IRGN_WT (1 << 0 | 0 << 6) > +#define TTBR0_IRGN_WB (1 << 0 | 1 << 6) > +#endif > + > /** > * Change the cache settings for a region. > * > diff --git a/arch/arm/lib/cache-cp15.c b/arch/arm/lib/cache-cp15.c > index 0291afa..c65e068 100644 > --- a/arch/arm/lib/cache-cp15.c > +++ b/arch/arm/lib/cache-cp15.c > @@ -96,9 +96,23 @@ static inline void mmu_setup(void) > dram_bank_mmu_setup(i); > } > > +#ifdef CONFIG_ARMV7 > + /* Set TTBR0 */ > + reg = gd->arch.tlb_addr & TTBR0_BASE_ADDR_MASK; > +#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH) > + reg |= TTBR0_RGN_WT | TTBR0_IRGN_WT; > +#elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC) > + reg |= TTBR0_RGN_WBWA | TTBR0_IRGN_WBWA; > +#else > + reg |= TTBR0_RGN_WB | TTBR0_IRGN_WB; > +#endif > + asm volatile("mcr p15, 0, %0, c2, c0, 0" > + : : "r" (reg) : "memory"); > +#else > /* Copy the page table address to cp15 */ > asm volatile("mcr p15, 0, %0, c2, c0, 0" > : : "r" (gd->arch.tlb_addr) : "memory"); > +#endif > /* Set the access control to all-supervisor */ > asm volatile("mcr p15, 0, %0, c3, c0, 0" > : : "r" (~0)); > -- > 1.9.1 > > _______________________________________________ > U-Boot mailing list > U-Boot at lists.denx.de > http://lists.denx.de/mailman/listinfo/u-boot Applied to u-boot-arm/master, thanks! Amicalement, -- Albert.