[U-Boot] [PATCH v2] arm: socfpga: fix SPL booting from fpga OnChip RAM

[Simon Goldschmidt]

This patch prevents disabling the FPGA bridges when
SPL or U-Boot is executed from FPGA onchip RAM.

Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt at gmail.com>
---

Changes in v2:
- use less ifdefs and more C code for address checks
  (but this gives a checkpatch warning because of comparing two
  upper case constants)
- changed comments

This patch depends on:
- CONFIG_SPL_TEXT_BASE needs to be set to 0xC0000000
  ideally this is done by moving SPL_TEXT_BASE to Kconfig:
  https://patchwork.ozlabs.org/patch/976918/
---
 arch/arm/mach-socfpga/include/mach/base_addr_ac5.h |  1 +
 arch/arm/mach-socfpga/misc_gen5.c                  | 13 ++++++++++++-
 arch/arm/mach-socfpga/spl_gen5.c                   | 10 +++++++---
 3 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-socfpga/include/mach/base_addr_ac5.h b/arch/arm/mach-socfpga/include/mach/base_addr_ac5.h
index bb9e3faa29..2725e9fcc3 100644
--- a/arch/arm/mach-socfpga/include/mach/base_addr_ac5.h
+++ b/arch/arm/mach-socfpga/include/mach/base_addr_ac5.h
@@ -6,6 +6,7 @@
 #ifndef _SOCFPGA_BASE_ADDRS_H_
 #define _SOCFPGA_BASE_ADDRS_H_
 
+#define SOCFPGA_FPGA_SLAVES_ADDRESS	0xc0000000
 #define SOCFPGA_STM_ADDRESS		0xfc000000
 #define SOCFPGA_DAP_ADDRESS		0xff000000
 #define SOCFPGA_EMAC0_ADDRESS		0xff700000
diff --git a/arch/arm/mach-socfpga/misc_gen5.c b/arch/arm/mach-socfpga/misc_gen5.c
index 429c3d6cd5..b35636b590 100644
--- a/arch/arm/mach-socfpga/misc_gen5.c
+++ b/arch/arm/mach-socfpga/misc_gen5.c
@@ -177,6 +177,8 @@ static void socfpga_nic301_slave_ns(void)
 
 void socfpga_sdram_remap_zero(void)
 {
+	u32 remap;
+
 	socfpga_nic301_slave_ns();
 
 	/*
@@ -187,7 +189,16 @@ void socfpga_sdram_remap_zero(void)
 	setbits_le32(&scu_regs->sacr, 0xfff);
 
 	/* Configure the L2 controller to make SDRAM start at 0 */
-	writel(0x1, &nic301_regs->remap);	/* remap.mpuzero */
+	remap = 0x1; /* remap.mpuzero */
+	if (CONFIG_SYS_TEXT_BASE >= SOCFPGA_FPGA_SLAVES_ADDRESS &&
+	    CONFIG_SYS_TEXT_BASE < SOCFPGA_STM_ADDRESS)
+		remap |= 0x8; /* remap.hps2fpga: keep fpga bridge enabled */
+#ifdef CONFIG_SPL_BUILD
+	if (CONFIG_SPL_TEXT_BASE == SOCFPGA_FPGA_SLAVES_ADDRESS)
+		remap |= 0x8; /* remap.hps2fpga: keep fpga bridge enabled */
+#endif
+	writel(remap, &nic301_regs->remap);
+
 	writel(0x1, &pl310->pl310_addr_filter_start);
 }
 
diff --git a/arch/arm/mach-socfpga/spl_gen5.c b/arch/arm/mach-socfpga/spl_gen5.c
index be318cc0d9..5c3995be13 100644
--- a/arch/arm/mach-socfpga/spl_gen5.c
+++ b/arch/arm/mach-socfpga/spl_gen5.c
@@ -92,8 +92,11 @@ void board_init_f(ulong dummy)
 
 	/* Put everything into reset but L4WD0. */
 	socfpga_per_reset_all();
-	/* Put FPGA bridges into reset too. */
-	socfpga_bridges_reset(1);
+
+	if (CONFIG_SPL_TEXT_BASE != SOCFPGA_FPGA_SLAVES_ADDRESS) {
+		/* Put FPGA bridges into reset (unless booting from FPGA). */
+		socfpga_bridges_reset(1);
+	}
 
 	socfpga_per_reset(SOCFPGA_RESET(SDR), 0);
 	socfpga_per_reset(SOCFPGA_RESET(UART0), 0);
@@ -163,5 +166,6 @@ void board_init_f(ulong dummy)
 		hang();
 	}
 
-	socfpga_bridges_reset(1);
+	if (CONFIG_SPL_TEXT_BASE != SOCFPGA_FPGA_SLAVES_ADDRESS)
+		socfpga_bridges_reset(1);
 }
-- 
2.17.1