ARM64: zynqmp: Add support for standard distro boot commands

Nand and QSPI are not defined now but this will be extended. Based on selected bootmode boot_targets are rewritten. Patch also contains detection if variables are saved. If yes don't rewrite boot_targets variable.

Also move variable setup to the end of file because SCSI needs to be defined before others macros are using it.

Signed-off-by Michal Simek <[email protected]>

---

Changes in v2:
- Append default boot_targets to the list

Patch depends on
"env: Setup GD_FLG_ENV_DEFAULT flag when default environment are used"

---
 board/xilinx/zynqmp/zynqmp.c    | 27 ++++++++++++++-----
 include/configs/xilinx_zynqmp.h | 59 ++++++++++++++++++++++++++++++-----------
 2 files changed, 64 insertions(+), 22 deletions(-)

board/xilinx/zynqmp/zynqmp.c +5 -0

index 4623cd49e9c7..204f8c526ab4 100644
@@ -215,6 +215,11 @@ int board_late_init(void)
 	u32 reg = 0;
 	u8 bootmode;
 
+	if (!(gd->flags & GD_FLG_ENV_DEFAULT)) {
+		debug("Saved variables - Skipping\n");
+		return 0;
+	}
+
 	reg = readl(&crlapb_base->boot_mode);
 	bootmode = reg & BOOT_MODES_MASK;
 

Quoted 39 lines · Michal Simek

Nand and QSPI are not defined now but this will be extended. Based on selected bootmode boot_targets are rewritten. Patch also contains detection if variables are saved. If yes don't rewrite boot_targets variable.

Also move variable setup to the end of file because SCSI needs to be defined before others macros are using it.

Signed-off-by Michal Simek <[email protected]>

---

Changes in v2:
- Append default boot_targets to the list

Patch depends on
"env: Setup GD_FLG_ENV_DEFAULT flag when default environment are used"

---
 board/xilinx/zynqmp/zynqmp.c    | 27 ++++++++++++++-----
 include/configs/xilinx_zynqmp.h | 59 ++++++++++++++++++++++++++++++-----------
 2 files changed, 64 insertions(+), 22 deletions(-)

board/xilinx/zynqmp/zynqmp.c +5 -0

index 4623cd49e9c7..204f8c526ab4 100644
@@ -215,6 +215,11 @@ int board_late_init(void)
 	u32 reg = 0;
 	u8 bootmode;
 
+	if (!(gd->flags & GD_FLG_ENV_DEFAULT)) {
+		debug("Saved variables - Skipping\n");
+		return 0;
+	}
+
 	reg = readl(&crlapb_base->boot_mode);
 	bootmode = reg & BOOT_MODES_MASK;
 

board/xilinx/zynqmp/zynqmp.c int board_late_init(void) · line 231

Quoted 6 lines

board/xilinx/zynqmp/zynqmp.c +2 -1

@@ -222,31 +227,39 @@ int board_late_init(void)
 	switch (bootmode) {
 	case JTAG_MODE:
 		puts("JTAG_MODE\n");
-		setenv("modeboot", "jtagboot");
+		setenv("boot_targets", strcat("pxe dhcp ",
+					      getenv("boot_targets")));

The strcat() function appends the src string to the dest
string, overwriting the terminating null byte ('\0') at the end of dest, and then adds a terminating null byte. The strings may
not overlap, and the dest string must have enough space for the
result. If dest is not large enough, program behavior is unpredictable; buffer overruns are a favorite avenue for attacking
secure programs.

---

In other words, the code above creates a buffer overflow :). You need something like

const char *new_targets = "pxe dhcp"; // <- make this a parameter to a
function

new_targets = malloc(strlen(new_targets) +
strlen(getenv("boot_targets") + 2); // one byte for the space, one for the null-terminator
sprintf(new_targets, "%s %s", new_targets, boot_targets); setenv("boot_targets", new_targets);

Isn't string handling in C awesome? It's almost as readable and easy as doing it in assembly.