zynqmp: spl: support DRAM ECC initialization
authorJorge Ramirez-Ortiz <jorge@foundries.io>
Sun, 13 Jun 2021 18:55:53 +0000 (20:55 +0200)
committerMichal Simek <michal.simek@xilinx.com>
Wed, 23 Jun 2021 07:48:35 +0000 (09:48 +0200)
Use the ZDMA channel 0 to initialize the DRAM banks. This avoid
spurious ECC errors that can occur when accessing unitialized memory.

The feature is enabled by setting the option
CONFIG_SPL_ZYNQMP_DRAM_ECC_INIT and providing the following data:

 SPL_ZYNQMP_DRAM_BANK1_BASE: start of memory to initialize
 SPL_ZYNQMP_DRAM_BANK1_LEN : len of memory to initialize (hex)
 SPL_ZYNQMP_DRAM_BANK2_BASE: start of memory to initialize
 SPL_ZYNQMP_DRAM_BANK2_LEN : len of memory to initialize (hex)

Setting SPL_ZYNQMP_DRAM_BANK_LEN to 0 takes no action.

Signed-off-by: Jorge Ramirez-Ortiz <jorge@foundries.io>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
arch/arm/mach-zynqmp/Kconfig
arch/arm/mach-zynqmp/Makefile
arch/arm/mach-zynqmp/ecc_spl_init.c [new file with mode: 0644]
arch/arm/mach-zynqmp/include/mach/ecc_spl_init.h [new file with mode: 0644]
arch/arm/mach-zynqmp/include/mach/hardware.h
arch/arm/mach-zynqmp/spl.c

index f1301f6..39144d6 100644 (file)
@@ -92,6 +92,41 @@ config ZYNQMP_NO_DDR
          This option configures MMU with no DDR to avoid speculative
          access to DDR memory where DDR is not present.
 
+config SPL_ZYNQMP_DRAM_ECC_INIT
+       bool "Initialize DRAM ECC"
+       depends on SPL
+       help
+         This option initializes all memory to 0xdeadbeef. Must be set if your
+         memory is of ECC type.
+
+config SPL_ZYNQMP_DRAM_BANK1_BASE
+       depends on SPL_ZYNQMP_DRAM_ECC_INIT
+       hex "DRAM Bank1 address"
+       default 0x00000000
+       help
+         Start address of DRAM ECC bank1
+
+config SPL_ZYNQMP_DRAM_BANK1_LEN
+       depends on SPL_ZYNQMP_DRAM_ECC_INIT
+       hex "DRAM Bank1 size"
+       default 0x80000000
+       help
+         Size in bytes of the DRAM ECC bank1
+
+config SPL_ZYNQMP_DRAM_BANK2_BASE
+       depends on SPL_ZYNQMP_DRAM_ECC_INIT
+       hex "DRAM Bank2 address"
+       default 0x800000000
+       help
+         Start address of DRAM ECC bank2
+
+config SPL_ZYNQMP_DRAM_BANK2_LEN
+       depends on SPL_ZYNQMP_DRAM_ECC_INIT
+       hex "DRAM Bank2 size"
+       default 0x0
+       help
+         Size in bytes of the DRAM ECC bank2. A null size takes no action.
+
 config SYS_MALLOC_F_LEN
        default 0x600
 
index 8a3b074..eb6c511 100644 (file)
@@ -7,4 +7,5 @@ obj-y   += clk.o
 obj-y  += cpu.o
 obj-$(CONFIG_MP)       += mp.o
 obj-$(CONFIG_SPL_BUILD) += spl.o handoff.o
+obj-$(CONFIG_SPL_ZYNQMP_DRAM_ECC_INIT) += ecc_spl_init.o
 obj-$(CONFIG_ZYNQMP_PSU_INIT_ENABLED)  += psu_spl_init.o
diff --git a/arch/arm/mach-zynqmp/ecc_spl_init.c b/arch/arm/mach-zynqmp/ecc_spl_init.c
new file mode 100644 (file)
index 0000000..f547d8e
--- /dev/null
@@ -0,0 +1,163 @@
+// SPDX-License-Identifier: MIT
+/*
+ *  Copyright(c) 2015 - 2020 Xilinx, Inc.
+ *
+ *  Jorge Ramirez-Ortiz <jorge@foundries.io>
+ */
+
+#include <common.h>
+#include <cpu_func.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/ecc_spl_init.h>
+#include <asm/io.h>
+#include <linux/delay.h>
+
+#define ZDMA_TRANSFER_MAX_LEN          (0x3FFFFFFFU - 7U)
+#define ZDMA_CH_STATUS                 ((ADMA_CH0_BASEADDR) + 0x0000011CU)
+#define ZDMA_CH_STATUS_STATE_MASK      0x00000003U
+#define ZDMA_CH_STATUS_STATE_DONE      0x00000000U
+#define ZDMA_CH_STATUS_STATE_ERR       0x00000003U
+#define ZDMA_CH_CTRL0                  ((ADMA_CH0_BASEADDR) + 0x00000110U)
+#define ZDMA_CH_CTRL0_POINT_TYPE_MASK  (u32)0x00000040U
+#define ZDMA_CH_CTRL0_POINT_TYPE_NORMAL        (u32)0x00000000U
+#define ZDMA_CH_CTRL0_MODE_MASK                (u32)0x00000030U
+#define ZDMA_CH_CTRL0_MODE_WR_ONLY     (u32)0x00000010U
+#define ZDMA_CH_CTRL0_TOTAL_BYTE_COUNT ((ADMA_CH0_BASEADDR) + 0x00000188U)
+#define ZDMA_CH_WR_ONLY_WORD0          ((ADMA_CH0_BASEADDR) + 0x00000148U)
+#define ZDMA_CH_WR_ONLY_WORD1          ((ADMA_CH0_BASEADDR) + 0x0000014CU)
+#define ZDMA_CH_WR_ONLY_WORD2          ((ADMA_CH0_BASEADDR) + 0x00000150U)
+#define ZDMA_CH_WR_ONLY_WORD3          ((ADMA_CH0_BASEADDR) + 0x00000154U)
+#define ZDMA_CH_DST_DSCR_WORD0         ((ADMA_CH0_BASEADDR) + 0x00000138U)
+#define ZDMA_CH_DST_DSCR_WORD0_LSB_MASK        0xFFFFFFFFU
+#define ZDMA_CH_DST_DSCR_WORD1         ((ADMA_CH0_BASEADDR) + 0x0000013CU)
+#define ZDMA_CH_DST_DSCR_WORD1_MSB_MASK        0x0001FFFFU
+#define ZDMA_CH_SRC_DSCR_WORD2         ((ADMA_CH0_BASEADDR) + 0x00000130U)
+#define ZDMA_CH_DST_DSCR_WORD2         ((ADMA_CH0_BASEADDR) + 0x00000140U)
+#define ZDMA_CH_CTRL2                  ((ADMA_CH0_BASEADDR) + 0x00000200U)
+#define ZDMA_CH_CTRL2_EN_MASK          0x00000001U
+#define ZDMA_CH_ISR                    ((ADMA_CH0_BASEADDR) + 0x00000100U)
+#define ZDMA_CH_ISR_DMA_DONE_MASK      0x00000400U
+#define ECC_INIT_VAL_WORD              0xDEADBEEFU
+
+#define ZDMA_IDLE_TIMEOUT_USEC         1000000
+#define ZDMA_DONE_TIMEOUT_USEC         5000000
+
+static void ecc_zdma_restore(void)
+{
+       /* Restore reset values for the DMA registers used */
+       writel(ZDMA_CH_CTRL0, 0x00000080U);
+       writel(ZDMA_CH_WR_ONLY_WORD0, 0x00000000U);
+       writel(ZDMA_CH_WR_ONLY_WORD1, 0x00000000U);
+       writel(ZDMA_CH_WR_ONLY_WORD2, 0x00000000U);
+       writel(ZDMA_CH_WR_ONLY_WORD3, 0x00000000U);
+       writel(ZDMA_CH_DST_DSCR_WORD0, 0x00000000U);
+       writel(ZDMA_CH_DST_DSCR_WORD1, 0x00000000U);
+       writel(ZDMA_CH_SRC_DSCR_WORD2, 0x00000000U);
+       writel(ZDMA_CH_DST_DSCR_WORD2, 0x00000000U);
+       writel(ZDMA_CH_CTRL0_TOTAL_BYTE_COUNT, 0x00000000U);
+}
+
+static void ecc_dram_bank_init(u64 addr, u64 len)
+{
+       bool retry = true;
+       u32 timeout;
+       u64 bytes;
+       u32 size;
+       u64 src;
+       u32 reg;
+
+       if (!len)
+               return;
+retry:
+       bytes = len;
+       src = addr;
+       ecc_zdma_restore();
+       while (bytes > 0) {
+               size = bytes > ZDMA_TRANSFER_MAX_LEN ?
+                       ZDMA_TRANSFER_MAX_LEN : (u32)bytes;
+
+               /* Wait until the DMA is in idle state */
+               timeout = ZDMA_IDLE_TIMEOUT_USEC;
+               do {
+                       udelay(1);
+                       reg = readl(ZDMA_CH_STATUS);
+                       reg &= ZDMA_CH_STATUS_STATE_MASK;
+                       if (!timeout--) {
+                               puts("error, ECC DMA failed to idle\n");
+                               goto done;
+                       }
+
+               } while ((reg != ZDMA_CH_STATUS_STATE_DONE) &&
+                       (reg != ZDMA_CH_STATUS_STATE_ERR));
+
+               /* Enable Simple (Write Only) Mode */
+               reg = readl(ZDMA_CH_CTRL0);
+               reg &= (ZDMA_CH_CTRL0_POINT_TYPE_MASK |
+                       ZDMA_CH_CTRL0_MODE_MASK);
+               reg |= (ZDMA_CH_CTRL0_POINT_TYPE_NORMAL |
+                       ZDMA_CH_CTRL0_MODE_WR_ONLY);
+               writel(reg, ZDMA_CH_CTRL0);
+
+               /* Fill in the data to be written */
+               writel(ECC_INIT_VAL_WORD, ZDMA_CH_WR_ONLY_WORD0);
+               writel(ECC_INIT_VAL_WORD, ZDMA_CH_WR_ONLY_WORD1);
+               writel(ECC_INIT_VAL_WORD, ZDMA_CH_WR_ONLY_WORD2);
+               writel(ECC_INIT_VAL_WORD, ZDMA_CH_WR_ONLY_WORD3);
+
+               /* Write Destination Address */
+               writel((u32)(src & ZDMA_CH_DST_DSCR_WORD0_LSB_MASK),
+                      ZDMA_CH_DST_DSCR_WORD0);
+               writel((u32)((src >> 32) & ZDMA_CH_DST_DSCR_WORD1_MSB_MASK),
+                      ZDMA_CH_DST_DSCR_WORD1);
+
+               /* Size to be Transferred. Recommended to set both src and dest sizes */
+               writel(size, ZDMA_CH_SRC_DSCR_WORD2);
+               writel(size, ZDMA_CH_DST_DSCR_WORD2);
+
+               /* DMA Enable */
+               reg = readl(ZDMA_CH_CTRL2);
+               reg |= ZDMA_CH_CTRL2_EN_MASK;
+               writel(reg, ZDMA_CH_CTRL2);
+
+               /* Check the status of the transfer by polling on DMA Done */
+               timeout = ZDMA_DONE_TIMEOUT_USEC;
+               do {
+                       udelay(1);
+                       reg = readl(ZDMA_CH_ISR);
+                       reg &= ZDMA_CH_ISR_DMA_DONE_MASK;
+                       if (!timeout--) {
+                               puts("error, ECC DMA timeout\n");
+                               goto done;
+                       }
+               } while (reg != ZDMA_CH_ISR_DMA_DONE_MASK);
+
+               /* Clear DMA status */
+               reg = readl(ZDMA_CH_ISR);
+               reg |= ZDMA_CH_ISR_DMA_DONE_MASK;
+               writel(ZDMA_CH_ISR_DMA_DONE_MASK, ZDMA_CH_ISR);
+
+               /* Read the channel status for errors */
+               reg = readl(ZDMA_CH_STATUS);
+               if (reg == ZDMA_CH_STATUS_STATE_ERR) {
+                       if (retry) {
+                               retry = false;
+                               goto retry;
+                       }
+                       puts("error, ECC DMA error\n");
+                       break;
+               }
+
+               bytes -= size;
+               src += size;
+       }
+done:
+       ecc_zdma_restore();
+}
+
+void zynqmp_ecc_init(void)
+{
+       ecc_dram_bank_init(CONFIG_SPL_ZYNQMP_DRAM_BANK1_BASE,
+                          CONFIG_SPL_ZYNQMP_DRAM_BANK1_LEN);
+       ecc_dram_bank_init(CONFIG_SPL_ZYNQMP_DRAM_BANK2_BASE,
+                          CONFIG_SPL_ZYNQMP_DRAM_BANK2_LEN);
+}
diff --git a/arch/arm/mach-zynqmp/include/mach/ecc_spl_init.h b/arch/arm/mach-zynqmp/include/mach/ecc_spl_init.h
new file mode 100644 (file)
index 0000000..b4b6fcf
--- /dev/null
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ *  Copyright(c) 2015 - 2020 Xilinx, Inc.
+ *
+ *  Jorge Ramirez-Ortiz <jorge@foundries.io>
+ */
+
+#ifndef __ARCH_ZYNQMP_ECC_INIT_H
+#define __ARCH_ZYNQMP_ECC_INIT_H
+
+void zynqmp_ecc_init(void);
+
+#endif
index a798aa0..3776499 100644 (file)
@@ -24,6 +24,8 @@
                                                            + 0x00000114)
 #define ZYNQMP_PS_SYSMON_ANALOG_BUS_VAL 0x00003210
 
+#define ADMA_CH0_BASEADDR      0xFFA80000
+
 #define PS_MODE0       BIT(0)
 #define PS_MODE1       BIT(1)
 #define PS_MODE2       BIT(2)
index 88386b2..8fcae2c 100644 (file)
@@ -15,6 +15,7 @@
 #include <asm/io.h>
 #include <asm/spl.h>
 #include <asm/arch/hardware.h>
+#include <asm/arch/ecc_spl_init.h>
 #include <asm/arch/psu_init_gpl.h>
 #include <asm/arch/sys_proto.h>
 
@@ -22,6 +23,9 @@ void board_init_f(ulong dummy)
 {
        board_early_init_f();
        board_early_init_r();
+#ifdef CONFIG_SPL_ZYNQMP_DRAM_ECC_INIT
+       zynqmp_ecc_init();
+#endif
 }
 
 static void ps_mode_reset(ulong mode)