- doc: fix code examples in qemu-mips.rst

- mips: vcoreiii: fix memtest and cache coherency issues
 - cmd/go: fix cache coherency issues on MIPS
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Merge tag 'mips-fixes-for-2020.04' of git://git.denx.de/u-boot-mips

- doc: fix code examples in qemu-mips.rst
- mips: vcoreiii: fix memtest and cache coherency issues
- cmd/go: fix cache coherency issues on MIPS

arch/mips/cpu/time.c

@@ -13,7 +13,7 @@ unsigned long notrace timer_read_counter(void)
 	return read_c0_count();
 }
 
-ulong notrace get_tbclk(void)
+ulong notrace __weak get_tbclk(void)
 {
 	return CONFIG_SYS_MIPS_TIMER_FREQ;
 }

arch/mips/lib/Makefile

@@ -11,5 +11,6 @@ obj-y	+= stack.o
 obj-y	+= traps.o
 
 obj-$(CONFIG_CMD_BOOTM) += bootm.o
+obj-$(CONFIG_CMD_GO) += boot.o
 
 lib-$(CONFIG_USE_PRIVATE_LIBGCC) += ashldi3.o ashrdi3.o lshrdi3.o

arch/mips/lib/boot.c

@@ -0,0 +1,23 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2020 Stefan Roese <sr@denx.de>
+ */
+
+#include <common.h>
+#include <command.h>
+#include <cpu_func.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+unsigned long do_go_exec(ulong (*entry)(int, char * const []),
+			 int argc, char * const argv[])
+{
+	/*
+	 * Flush cache before jumping to application. Let's flush the
+	 * whole SDRAM area, since we don't know the size of the image
+	 * that was loaded.
+	 */
+	flush_cache(gd->bd->bi_memstart, gd->ram_top - gd->bd->bi_memstart);
+
+	return entry(argc, argv);
+}

arch/mips/lib/cache.c

@@ -141,7 +141,7 @@ ops_done:
 	instruction_hazard_barrier();
 }
 
-void flush_dcache_range(ulong start_addr, ulong stop)
+void __weak flush_dcache_range(ulong start_addr, ulong stop)
 {
 	unsigned long lsize = dcache_line_size();
 	unsigned long slsize = scache_line_size();

arch/mips/mach-mscc/cpu.c

@@ -7,6 +7,7 @@
 
 #include <asm/io.h>
 #include <asm/types.h>
+#include <asm/mipsregs.h>
 
 #include <mach/tlb.h>
 #include <mach/ddr.h>
@@ -53,7 +54,6 @@ void vcoreiii_tlb_init(void)
 		   MMU_REGIO_RW);
 #endif
 
-#if  CONFIG_SYS_TEXT_BASE == MSCC_FLASH_TO
 	/*
 	 * If U-Boot is located in NOR then we want to be able to use
 	 * the data cache in order to boot in a decent duration
@@ -71,9 +71,10 @@ void vcoreiii_tlb_init(void)
 	create_tlb(tlbix++, MSCC_DDR_TO, MSCC_RAM_TLB_SIZE, MMU_REGIO_RW,
 		   MSCC_ATTRIB2);
 
-	/* Enable caches by clearing the bit ERL, which is set on reset */
+	/* Enable mapping (using TLB) kuseg by clearing the bit ERL,
-	write_c0_status(read_c0_status() & ~BIT(2));
+	 * which is set on reset.
-#endif /* CONFIG_SYS_TEXT_BASE */
+	 */
+	write_c0_status(read_c0_status() & ~ST0_ERL);
 }
 
 int mach_cpu_init(void)

arch/mips/mach-mscc/dram.c

@@ -31,7 +31,7 @@ static inline int vcoreiii_train_bytelane(void)
 
 int vcoreiii_ddr_init(void)
 {
-	int res;
+	register int res;
 
 	if (!(readl(BASE_CFG + ICPU_MEMCTRL_STAT)
 	      & ICPU_MEMCTRL_STAT_INIT_DONE)) {
@@ -40,20 +40,19 @@ int vcoreiii_ddr_init(void)
 		if (hal_vcoreiii_init_dqs() || vcoreiii_train_bytelane())
 			hal_vcoreiii_ddr_failed();
 	}
-#if (CONFIG_SYS_TEXT_BASE != 0x20000000)
+
 	res = dram_check();
 	if (res == 0)
 		hal_vcoreiii_ddr_verified();
 	else
 		hal_vcoreiii_ddr_failed();
 
-	/* Clear boot-mode and read-back to activate/verify */
+	/*  Remap DDR to kuseg: Clear boot-mode */
 	clrbits_le32(BASE_CFG + ICPU_GENERAL_CTRL,
 		     ICPU_GENERAL_CTRL_BOOT_MODE_ENA);
+	/* - and read-back to activate/verify */
 	readl(BASE_CFG + ICPU_GENERAL_CTRL);
-#else
+
-	res = 0;
-#endif
 	return res;
 }
 
@@ -66,9 +65,6 @@ int print_cpuinfo(void)
 
 int dram_init(void)
 {
-	while (vcoreiii_ddr_init())
-		;
-
 	gd->ram_size = CONFIG_SYS_SDRAM_SIZE;
 	return 0;
 }

arch/mips/mach-mscc/include/mach/ddr.h

@@ -435,16 +435,12 @@ static inline void hal_vcoreiii_ddr_failed(void)
 	reset = KSEG0ADDR(_machine_restart);
 	icache_lock((void *)reset, 128);
 	asm volatile ("jr %0"::"r" (reset));
-
-	panic("DDR init failed\n");
 }
 #else				/* JR2 || ServalT */
 static inline void hal_vcoreiii_ddr_failed(void)
 {
 	writel(0, BASE_CFG + ICPU_RESET);
 	writel(PERF_SOFT_RST_SOFT_CHIP_RST, BASE_CFG + PERF_SOFT_RST);
-
-	panic("DDR init failed\n");
 }
 #endif
 

arch/mips/mach-mscc/lowlevel_init.S

@@ -8,6 +8,7 @@
 
     .set noreorder
     .extern     vcoreiii_tlb_init
+    .extern     vcoreiii_ddr_init
 #ifdef CONFIG_SOC_LUTON
     .extern     pll_init
 #endif
@@ -17,14 +18,28 @@ LEAF(lowlevel_init)
 	 * As we have no stack yet, we can assume the restricted
 	 * luxury of the sX-registers without saving them
 	 */
-	move	s0,ra
+
+	/* Modify ra/s0 such we return to physical NOR location */
+	li	t0, 0x0fffffff
+	li	t1, CONFIG_SYS_TEXT_BASE
+	and	s0, ra, t0
+	add	s0, s0, t1
 
 	jal	vcoreiii_tlb_init
 	 nop
+
 #ifdef CONFIG_SOC_LUTON
 	jal	pll_init
 	 nop
 #endif
+
+	/* Initialize DDR controller to enable stack/gd/heap */
+0:
+	jal	vcoreiii_ddr_init
+	 nop
+	bnez	v0, 0b		/* Retry on error */
+	 nop
+
 	jr	s0
 	 nop
 	END(lowlevel_init)

doc/board/emulation/qemu-mips.rst

@@ -25,37 +25,45 @@ Example usage
 
 Using u-boot.bin as ROM (replaces Qemu monitor):
 
-32 bit, big endian::
+32 bit, big endian
 
-   # make qemu_mips
+.. code-block:: bash
-   # qemu-system-mips -M mips -bios u-boot.bin -nographic
 
-32 bit, little endian::
+   make qemu_mips
+   qemu-system-mips -M mips -bios u-boot.bin -nographic
 
-   # make qemu_mipsel
+32 bit, little endian
-   # qemu-system-mipsel -M mips -bios u-boot.bin -nographic
 
-64 bit, big endian::
+.. code-block:: bash
 
-   # make qemu_mips64
+   make qemu_mipsel
-   # qemu-system-mips64 -cpu MIPS64R2-generic -M mips -bios u-boot.bin -nographic
+   qemu-system-mipsel -M mips -bios u-boot.bin -nographic
 
-64 bit, little endian::
+64 bit, big endian
 
-   # make qemu_mips64el
+.. code-block:: bash
-   # qemu-system-mips64el -cpu MIPS64R2-generic -M mips -bios u-boot.bin -nographic
+
+   make qemu_mips64
+   qemu-system-mips64 -cpu MIPS64R2-generic -M mips -bios u-boot.bin -nographic
+
+64 bit, little endian
+
+.. code-block:: bash
+
+   make qemu_mips64el
+   qemu-system-mips64el -cpu MIPS64R2-generic -M mips -bios u-boot.bin -nographic
 
 or using u-boot.bin from emulated flash:
 
-if you use a qemu version after commit 4224
+if you use a QEMU version after commit 4224
 
-.. code-block:: none
+.. code-block:: bash
 
-   create image:
+   # create image:
-   # dd of=flash bs=1k count=4k if=/dev/zero
+   dd of=flash bs=1k count=4k if=/dev/zero
-   # dd of=flash bs=1k conv=notrunc if=u-boot.bin
+   dd of=flash bs=1k conv=notrunc if=u-boot.bin
-   start it (see above):
+   # start it (see above):
-   # qemu-system-mips[64][el] [-cpu MIPS64R2-generic] -M mips -pflash flash -nographic
+   qemu-system-mips[64][el] [-cpu MIPS64R2-generic] -M mips -pflash flash -nographic
 
 Download kernel + initrd
 ^^^^^^^^^^^^^^^^^^^^^^^^
@@ -75,61 +83,63 @@ you can downland::
 Generate uImage
 ^^^^^^^^^^^^^^^
 
-.. code-block:: none
+.. code-block:: bash
 
-   # tools/mkimage -A mips -O linux -T kernel -C gzip -a 0x80010000 -e 0x80245650 -n "Linux 2.6.24.y" -d vmlinux.bin.gz uImage
+   tools/mkimage -A mips -O linux -T kernel -C gzip -a 0x80010000 -e 0x80245650 -n "Linux 2.6.24.y" -d vmlinux.bin.gz uImage
 
 Copy uImage to Flash
 ^^^^^^^^^^^^^^^^^^^^
 
-.. code-block:: none
+.. code-block:: bash
 
-   # dd if=uImage bs=1k conv=notrunc seek=224 of=flash
+   dd if=uImage bs=1k conv=notrunc seek=224 of=flash
 
 Generate Ide Disk
 ^^^^^^^^^^^^^^^^^
 
-.. code-block:: none
+.. code-block:: bash
 
-   # dd of=ide bs=1k cout=100k if=/dev/zero
+   dd of=ide bs=1k count=100k if=/dev/zero
 
-   # sfdisk -C 261 -d ide
+   # Create partion table
-   # partition table of ide
+   sudo sfdisk ide << EOF
+   label: dos
+   label-id: 0x6fe3a999
+   device: image
    unit: sectors
-
+   image1 : start=       63, size=    32067, Id=83
-        ide1 : start=       63, size=    32067, Id=83
+   image2 : start=    32130, size=    32130, Id=83
-        ide2 : start=    32130, size=    32130, Id=83
+   image3 : start=    64260, size=  4128705, Id=83
-        ide3 : start=    64260, size=  4128705, Id=83
+   EOF
-        ide4 : start=        0, size=        0, Id= 0
 
 Copy to ide
 ^^^^^^^^^^^
 
-.. code-block:: none
+.. code-block:: bash
 
-   # dd if=uImage bs=512 conv=notrunc seek=63 of=ide
+   dd if=uImage bs=512 conv=notrunc seek=63 of=ide
 
 Generate ext2 on part 2 on Copy uImage and initrd.gz
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-.. code-block:: none
+.. code-block:: bash
 
    # Attached as loop device ide offset = 32130 * 512
-   # losetup -o 16450560 -f ide
+   sudo losetup -o 16450560 /dev/loop0 ide
    # Format as ext2 ( arg2 : nb blocks)
-   # mke2fs /dev/loop0 16065
+   sudo mkfs.ext2 /dev/loop0 16065
-   # losetup -d /dev/loop0
+   sudo losetup -d /dev/loop0
    # Mount and copy uImage and initrd.gz to it
-   # mount -o loop,offset=16450560 -t ext2 ide /mnt
+   sudo mount -o loop,offset=16450560 -t ext2 ide /mnt
-   # mkdir /mnt/boot
+   sudo mkdir /mnt/boot
-   # cp {initrd.gz,uImage} /mnt/boot/
+   cp {initrd.gz,uImage} /mnt/boot/
    # Umount it
-   # umount /mnt
+   sudo umount /mnt
 
 Set Environment
 ^^^^^^^^^^^^^^^
 
-.. code-block:: none
+.. code-block:: bash
 
    setenv rd_start 0x80800000
    setenv rd_size 2663940
@@ -157,9 +167,11 @@ Set Environment
    setenv addmisc 'setenv bootargs ${bootargs} console=ttyS0,${baudrate} rd_start=${rd_start} rd_size=${rd_size} ethaddr=${ethaddr}'
    setenv bootcmd 'run boot_tftp_flash'
 
-Now you can boot from flash, ide, ide+ext2 and tfp::
+Now you can boot from flash, ide, ide+ext2 and tfp
 
-   # qemu-system-mips -M mips -pflash flash -monitor null -nographic -net nic -net user -tftp `pwd` -hda ide
+.. code-block:: bash
+
+   qemu-system-mips -M mips -pflash flash -monitor null -nographic -net nic -net user -tftp `pwd` -hda ide
 
 
 How to debug U-Boot
@@ -168,9 +180,9 @@ How to debug U-Boot
 In order to debug U-Boot you need to start qemu with gdb server support (-s)
 and waiting the connection to start the CPU (-S)
 
-.. code-block:: none
+.. code-block:: bash
 
-   # qemu-system-mips -S -s -M mips -pflash flash -monitor null -nographic -net nic -net user -tftp `pwd` -hda ide
+   qemu-system-mips -S -s -M mips -pflash flash -monitor null -nographic -net nic -net user -tftp `pwd` -hda ide
 
 in an other console you start gdb
 
@@ -182,7 +194,7 @@ by connecting to the gdb server localhost:1234
 
 .. code-block:: none
 
-   # mipsel-unknown-linux-gnu-gdb u-boot
+   $ mipsel-unknown-linux-gnu-gdb u-boot
    GNU gdb 6.6
    Copyright (C) 2006 Free Software Foundation, Inc.
    GDB is free software, covered by the GNU General Public License, and you are

include/configs/vcoreiii.h

@@ -39,7 +39,8 @@
 #define CONFIG_CONS_INDEX		1
 
 #define CONFIG_SYS_MEMTEST_START	CONFIG_SYS_SDRAM_BASE
-#define CONFIG_SYS_MEMTEST_END		(CONFIG_SYS_SDRAM_BASE + CONFIG_SYS_SDRAM_SIZE - SZ_1M)
+#define CONFIG_SYS_MEMTEST_END		(CONFIG_SYS_SDRAM_BASE + \
+					 CONFIG_SYS_SDRAM_SIZE - SZ_4M)
 
 #define CONFIG_SYS_MONITOR_BASE         CONFIG_SYS_TEXT_BASE