riscv: sbi: Add dbcn write test
Added a unit test for the RISC-V SBI debug console write() and
write_byte() functions. The output of the tests must be inspected
manually to verify that the correct bytes are written. For write(),
the expected output is 'DBCN_WRITE_TEST_STRING'. For write_byte(),
the expected output is 'a'.
Signed-off-by: Cade Richard <cade.richard@berkeley.edu>
[Applied all my suggested changes from the v4 review.]
Signed-off-by: Andrew Jones <andrew.jones@linux.dev>
diff --git a/lib/riscv/asm/sbi.h b/lib/riscv/asm/sbi.h
index 73ab543..47e9102 100644
--- a/lib/riscv/asm/sbi.h
+++ b/lib/riscv/asm/sbi.h
@@ -19,6 +19,7 @@
SBI_EXT_TIME = 0x54494d45,
SBI_EXT_HSM = 0x48534d,
SBI_EXT_SRST = 0x53525354,
+ SBI_EXT_DBCN = 0x4442434E,
};
enum sbi_ext_base_fid {
@@ -42,6 +43,12 @@
SBI_EXT_TIME_SET_TIMER = 0,
};
+enum sbi_ext_dbcn_fid {
+ SBI_EXT_DBCN_CONSOLE_WRITE = 0,
+ SBI_EXT_DBCN_CONSOLE_READ,
+ SBI_EXT_DBCN_CONSOLE_WRITE_BYTE,
+};
+
struct sbiret {
long error;
long value;
diff --git a/riscv/sbi.c b/riscv/sbi.c
index 2438c49..93a79d8 100644
--- a/riscv/sbi.c
+++ b/riscv/sbi.c
@@ -10,6 +10,7 @@
#include <asm/barrier.h>
#include <asm/csr.h>
#include <asm/delay.h>
+#include <asm/io.h>
#include <asm/isa.h>
#include <asm/processor.h>
#include <asm/sbi.h>
@@ -32,6 +33,19 @@
return sbi_ecall(SBI_EXT_TIME, SBI_EXT_TIME_SET_TIMER, stime_value, 0, 0, 0, 0, 0);
}
+static struct sbiret __dbcn_sbi_ecall(int fid, unsigned long arg0, unsigned long arg1, unsigned long arg2)
+{
+ return sbi_ecall(SBI_EXT_DBCN, fid, arg0, arg1, arg2, 0, 0, 0);
+}
+
+static void split_phys_addr(phys_addr_t paddr, unsigned long *hi, unsigned long *lo)
+{
+ *lo = (unsigned long)paddr;
+ *hi = 0;
+ if (__riscv_xlen == 32)
+ *hi = (unsigned long)(paddr >> 32);
+}
+
static bool env_or_skip(const char *env)
{
if (!getenv(env)) {
@@ -248,9 +262,69 @@
report_prefix_pop();
}
+#define DBCN_WRITE_TEST_STRING "DBCN_WRITE_TEST_STRING\n"
+#define DBCN_WRITE_BYTE_TEST_BYTE (u8)'a'
+
+/*
+ * Only the write functionality is tested here. There's no easy way to
+ * non-interactively test the read functionality.
+ */
+static void check_dbcn(void)
+{
+ unsigned long num_bytes, base_addr_lo, base_addr_hi;
+ phys_addr_t paddr;
+ int num_calls = 0;
+ struct sbiret ret;
+
+ report_prefix_push("dbcn");
+
+ ret = __base_sbi_ecall(SBI_EXT_BASE_PROBE_EXT, SBI_EXT_DBCN);
+ if (!ret.value) {
+ report_skip("DBCN extension unavailable");
+ report_prefix_pop();
+ return;
+ }
+
+ num_bytes = strlen(DBCN_WRITE_TEST_STRING);
+ paddr = virt_to_phys((void *)&DBCN_WRITE_TEST_STRING);
+ split_phys_addr(paddr, &base_addr_hi, &base_addr_lo);
+
+ report_prefix_push("write");
+
+ do {
+ ret = __dbcn_sbi_ecall(SBI_EXT_DBCN_CONSOLE_WRITE, num_bytes, base_addr_lo, base_addr_hi);
+ num_bytes -= ret.value;
+ paddr += ret.value;
+ split_phys_addr(paddr, &base_addr_hi, &base_addr_lo);
+ num_calls++;
+ } while (num_bytes != 0 && ret.error == SBI_SUCCESS);
+
+ report(ret.error == SBI_SUCCESS, "write success");
+ report_info("%d sbi calls made", num_calls);
+
+ /* Bytes are read from memory and written to the console */
+ if (env_or_skip("INVALID_ADDR")) {
+ paddr = strtoull(getenv("INVALID_ADDR"), NULL, 0);
+ split_phys_addr(paddr, &base_addr_hi, &base_addr_lo);
+ ret = __dbcn_sbi_ecall(SBI_EXT_DBCN_CONSOLE_WRITE, 1, base_addr_lo, base_addr_hi);
+ report(ret.error == SBI_ERR_INVALID_PARAM, "invalid parameter: address");
+ }
+
+ report_prefix_pop();
+
+ report_prefix_push("write_byte");
+
+ puts("DBCN_WRITE TEST CHAR: ");
+ ret = __dbcn_sbi_ecall(SBI_EXT_DBCN_CONSOLE_WRITE_BYTE, (u8)DBCN_WRITE_BYTE_TEST_BYTE, 0, 0);
+ puts("\n");
+ report(ret.error == SBI_SUCCESS, "write success");
+ report(ret.value == 0, "expected ret.value");
+
+ report_prefix_pop();
+}
+
int main(int argc, char **argv)
{
-
if (argc > 1 && !strcmp(argv[1], "-h")) {
help();
exit(0);
@@ -259,6 +333,7 @@
report_prefix_push("sbi");
check_base();
check_time();
+ check_dbcn();
return report_summary();
}
