arm: mach-k3: Enable dcache in SPL

Add support for enabling dcache already in SPL. It accelerates the boot
and resolves the risk to run into unaligned 64-bit accesses.

Based on original patch by Lokesh Vulta.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Lokesh Vutla <lokeshvutla@ti.com>
diff --git a/arch/arm/mach-k3/am6_init.c b/arch/arm/mach-k3/am6_init.c
index b692806..586f5c0 100644
--- a/arch/arm/mach-k3/am6_init.c
+++ b/arch/arm/mach-k3/am6_init.c
@@ -197,6 +197,7 @@
 	if (ret)
 		panic("DRAM init failed: %d\n", ret);
 #endif
+	spl_enable_dcache();
 }
 
 u32 spl_mmc_boot_mode(const u32 boot_device)
diff --git a/arch/arm/mach-k3/common.c b/arch/arm/mach-k3/common.c
index 80dfa5f..a94e054 100644
--- a/arch/arm/mach-k3/common.c
+++ b/arch/arm/mach-k3/common.c
@@ -406,3 +406,38 @@
 		}
 	}
 }
+
+void spl_enable_dcache(void)
+{
+#if !(defined(CONFIG_SYS_ICACHE_OFF) && defined(CONFIG_SYS_DCACHE_OFF))
+	phys_addr_t ram_top = CONFIG_SYS_SDRAM_BASE;
+
+	dram_init_banksize();
+
+	/* reserve TLB table */
+	gd->arch.tlb_size = PGTABLE_SIZE;
+
+	ram_top += get_effective_memsize();
+	/* keep ram_top in the 32-bit address space */
+	if (ram_top >= 0x100000000)
+		ram_top = (phys_addr_t) 0x100000000;
+
+	gd->arch.tlb_addr = ram_top - gd->arch.tlb_size;
+	debug("TLB table from %08lx to %08lx\n", gd->arch.tlb_addr,
+	      gd->arch.tlb_addr + gd->arch.tlb_size);
+
+	dcache_enable();
+#endif
+}
+
+#if !(defined(CONFIG_SYS_ICACHE_OFF) && defined(CONFIG_SYS_DCACHE_OFF))
+void spl_board_prepare_for_boot(void)
+{
+	dcache_disable();
+}
+
+void spl_board_prepare_for_boot_linux(void)
+{
+	dcache_disable();
+}
+#endif
diff --git a/arch/arm/mach-k3/common.h b/arch/arm/mach-k3/common.h
index 57682e1..94cdcb5 100644
--- a/arch/arm/mach-k3/common.h
+++ b/arch/arm/mach-k3/common.h
@@ -27,3 +27,4 @@
 void start_non_linux_remote_cores(void);
 int load_firmware(char *name_fw, char *name_loadaddr, u32 *loadaddr);
 void k3_sysfw_print_ver(void);
+void spl_enable_dcache(void);
diff --git a/arch/arm/mach-k3/j721e_init.c b/arch/arm/mach-k3/j721e_init.c
index 18a3c1c..031279b 100644
--- a/arch/arm/mach-k3/j721e_init.c
+++ b/arch/arm/mach-k3/j721e_init.c
@@ -221,6 +221,7 @@
 	if (ret)
 		panic("DRAM init failed: %d\n", ret);
 #endif
+	spl_enable_dcache();
 }
 
 u32 spl_mmc_boot_mode(const u32 boot_device)
diff --git a/board/ti/am65x/evm.c b/board/ti/am65x/evm.c
index a610879..2da7db9 100644
--- a/board/ti/am65x/evm.c
+++ b/board/ti/am65x/evm.c
@@ -69,11 +69,13 @@
 	/* Bank 0 declares the memory available in the DDR low region */
 	gd->bd->bi_dram[0].start = CONFIG_SYS_SDRAM_BASE;
 	gd->bd->bi_dram[0].size = 0x80000000;
+	gd->ram_size = 0x80000000;
 
 #ifdef CONFIG_PHYS_64BIT
 	/* Bank 1 declares the memory available in the DDR high region */
 	gd->bd->bi_dram[1].start = CONFIG_SYS_SDRAM_BASE1;
 	gd->bd->bi_dram[1].size = 0x80000000;
+	gd->ram_size = 0x100000000;
 #endif
 
 	return 0;