tests/pflash-cfi02: Add test for supported CFI commands

Test the AMD command set for parallel flash chips. This test uses an
ARM musicpal board with a pflash drive to test the following list of
currently-supported commands.
- Autoselect
- CFI
- Sector erase
- Chip erase
- Program
- Unlock bypass
- Reset

Signed-off-by: Stephen Checkoway <stephen.checkoway@oberlin.edu>
Message-Id: <20190426162624.55977-2-stephen.checkoway@oberlin.edu>
Acked-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
[PMD: reworded the patch subject, g_assert_cmpint -> cmphex]
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>

2 files changed, 227 insertions, 0 deletions

diff --git a/tests/Makefile.include b/tests/Makefile.include
index db750dd6d0..d02132fb94 100644
--- a/tests/Makefile.include
+++ b/tests/Makefile.include
@@ -260,6 +260,7 @@ check-qtest-arm-y += tests/m25p80-test$(EXESUF)
 check-qtest-arm-y += tests/test-arm-mptimer$(EXESUF)
 check-qtest-arm-y += tests/boot-serial-test$(EXESUF)
 check-qtest-arm-y += tests/hexloader-test$(EXESUF)
+check-qtest-arm-$(CONFIG_PFLASH_CFI02) += tests/pflash-cfi02-test$(EXESUF)
 
 check-qtest-aarch64-y = tests/numa-test$(EXESUF)
 check-qtest-aarch64-y += tests/boot-serial-test$(EXESUF)
@@ -767,6 +768,7 @@ tests/device-introspect-test$(EXESUF): tests/device-introspect-test.o
 tests/rtc-test$(EXESUF): tests/rtc-test.o
 tests/m48t59-test$(EXESUF): tests/m48t59-test.o
 tests/hexloader-test$(EXESUF): tests/hexloader-test.o
+tests/pflash-cfi02$(EXESUF): tests/pflash-cfi02-test.o
 tests/endianness-test$(EXESUF): tests/endianness-test.o
 tests/prom-env-test$(EXESUF): tests/prom-env-test.o $(libqos-obj-y)
 tests/rtas-test$(EXESUF): tests/rtas-test.o $(libqos-spapr-obj-y)
diff --git a/tests/pflash-cfi02-test.c b/tests/pflash-cfi02-test.c
new file mode 100644
index 0000000000..e7e16a8dd8
--- /dev/null
+++ b/tests/pflash-cfi02-test.c
@@ -0,0 +1,225 @@
+/*
+ * QTest testcase for parallel flash with AMD command set
+ *
+ * Copyright (c) 2019 Stephen Checkoway
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "libqtest.h"
+
+/*
+ * To test the pflash_cfi02 device, we run QEMU with the musicpal machine with
+ * a pflash drive. This enables us to test some flash configurations, but not
+ * all. In particular, we're limited to a 16-bit wide flash device.
+ */
+
+#define MP_FLASH_SIZE_MAX (32 * 1024 * 1024)
+#define BASE_ADDR (0x100000000ULL - MP_FLASH_SIZE_MAX)
+
+#define FLASH_WIDTH 2
+#define CFI_ADDR (FLASH_WIDTH * 0x55)
+#define UNLOCK0_ADDR (FLASH_WIDTH * 0x5555)
+#define UNLOCK1_ADDR (FLASH_WIDTH * 0x2AAA)
+
+#define CFI_CMD 0x98
+#define UNLOCK0_CMD 0xAA
+#define UNLOCK1_CMD 0x55
+#define AUTOSELECT_CMD 0x90
+#define RESET_CMD 0xF0
+#define PROGRAM_CMD 0xA0
+#define SECTOR_ERASE_CMD 0x30
+#define CHIP_ERASE_CMD 0x10
+#define UNLOCK_BYPASS_CMD 0x20
+#define UNLOCK_BYPASS_RESET_CMD 0x00
+
+static char image_path[] = "/tmp/qtest.XXXXXX";
+
+static inline void flash_write(uint64_t byte_addr, uint16_t data)
+{
+    qtest_writew(global_qtest, BASE_ADDR + byte_addr, data);
+}
+
+static inline uint16_t flash_read(uint64_t byte_addr)
+{
+    return qtest_readw(global_qtest, BASE_ADDR + byte_addr);
+}
+
+static void unlock(void)
+{
+    flash_write(UNLOCK0_ADDR, UNLOCK0_CMD);
+    flash_write(UNLOCK1_ADDR, UNLOCK1_CMD);
+}
+
+static void reset(void)
+{
+    flash_write(0, RESET_CMD);
+}
+
+static void sector_erase(uint64_t byte_addr)
+{
+    unlock();
+    flash_write(UNLOCK0_ADDR, 0x80);
+    unlock();
+    flash_write(byte_addr, SECTOR_ERASE_CMD);
+}
+
+static void wait_for_completion(uint64_t byte_addr)
+{
+    /* If DQ6 is toggling, step the clock and ensure the toggle stops. */
+    if ((flash_read(byte_addr) & 0x40) ^ (flash_read(byte_addr) & 0x40)) {
+        /* Wait for erase or program to finish. */
+        clock_step_next();
+        /* Ensure that DQ6 has stopped toggling. */
+        g_assert_cmphex(flash_read(byte_addr), ==, flash_read(byte_addr));
+    }
+}
+
+static void bypass_program(uint64_t byte_addr, uint16_t data)
+{
+    flash_write(UNLOCK0_ADDR, PROGRAM_CMD);
+    flash_write(byte_addr, data);
+    /*
+     * Data isn't valid until DQ6 stops toggling. We don't model this as
+     * writes are immediate, but if this changes in the future, we can wait
+     * until the program is complete.
+     */
+    wait_for_completion(byte_addr);
+}
+
+static void program(uint64_t byte_addr, uint16_t data)
+{
+    unlock();
+    bypass_program(byte_addr, data);
+}
+
+static void chip_erase(void)
+{
+    unlock();
+    flash_write(UNLOCK0_ADDR, 0x80);
+    unlock();
+    flash_write(UNLOCK0_ADDR, SECTOR_ERASE_CMD);
+}
+
+static void test_flash(void)
+{
+    global_qtest = qtest_initf("-M musicpal,accel=qtest "
+                               "-drive if=pflash,file=%s,format=raw,copy-on-read",
+                               image_path);
+    /* Check the IDs. */
+    unlock();
+    flash_write(UNLOCK0_ADDR, AUTOSELECT_CMD);
+    g_assert_cmphex(flash_read(FLASH_WIDTH * 0x0000), ==, 0x00BF);
+    g_assert_cmphex(flash_read(FLASH_WIDTH * 0x0001), ==, 0x236D);
+    reset();
+
+    /* Check the erase blocks. */
+    flash_write(CFI_ADDR, CFI_CMD);
+    g_assert_cmphex(flash_read(FLASH_WIDTH * 0x10), ==, 'Q');
+    g_assert_cmphex(flash_read(FLASH_WIDTH * 0x11), ==, 'R');
+    g_assert_cmphex(flash_read(FLASH_WIDTH * 0x12), ==, 'Y');
+    /* Num erase regions. */
+    g_assert_cmphex(flash_read(FLASH_WIDTH * 0x2C), >=, 1);
+    uint32_t nb_sectors = flash_read(FLASH_WIDTH * 0x2D) +
+                          (flash_read(FLASH_WIDTH * 0x2E) << 8) + 1;
+    uint32_t sector_len = (flash_read(FLASH_WIDTH * 0x2F) << 8) +
+                          (flash_read(FLASH_WIDTH * 0x30) << 16);
+    reset();
+
+    /* Erase and program sector. */
+    for (uint32_t i = 0; i < nb_sectors; ++i) {
+        uint64_t byte_addr = i * sector_len;
+        sector_erase(byte_addr);
+        /* Read toggle. */
+        uint16_t status0 = flash_read(byte_addr);
+        /* DQ7 is 0 during an erase. */
+        g_assert_cmphex(status0 & 0x80, ==, 0);
+        uint16_t status1 = flash_read(byte_addr);
+        /* DQ6 toggles during an erase. */
+        g_assert_cmphex(status0 & 0x40, !=, status1 & 0x40);
+        /* Wait for erase to complete. */
+        clock_step_next();
+        /* Ensure DQ6 has stopped toggling. */
+        g_assert_cmphex(flash_read(byte_addr), ==, flash_read(byte_addr));
+        /* Now the data should be valid. */
+        g_assert_cmphex(flash_read(byte_addr), ==, 0xFFFF);
+
+        /* Program a bit pattern. */
+        program(byte_addr, 0x5555);
+        g_assert_cmphex(flash_read(byte_addr), ==, 0x5555);
+        program(byte_addr, 0xAA55);
+        g_assert_cmphex(flash_read(byte_addr), ==, 0x0055);
+    }
+
+    /* Erase the chip. */
+    chip_erase();
+    /* Read toggle. */
+    uint16_t status0 = flash_read(0);
+    /* DQ7 is 0 during an erase. */
+    g_assert_cmphex(status0 & 0x80, ==, 0);
+    uint16_t status1 = flash_read(0);
+    /* DQ6 toggles during an erase. */
+    g_assert_cmphex(status0 & 0x40, !=, status1 & 0x40);
+    /* Wait for erase to complete. */
+    clock_step_next();
+    /* Ensure DQ6 has stopped toggling. */
+    g_assert_cmphex(flash_read(0), ==, flash_read(0));
+    /* Now the data should be valid. */
+    g_assert_cmphex(flash_read(0), ==, 0xFFFF);
+
+    /* Unlock bypass */
+    unlock();
+    flash_write(UNLOCK0_ADDR, UNLOCK_BYPASS_CMD);
+    bypass_program(0, 0x0123);
+    bypass_program(2, 0x4567);
+    bypass_program(4, 0x89AB);
+    /*
+     * Test that bypass programming, unlike normal programming can use any
+     * address for the PROGRAM_CMD.
+     */
+    flash_write(6, PROGRAM_CMD);
+    flash_write(6, 0xCDEF);
+    wait_for_completion(6);
+    flash_write(0, UNLOCK_BYPASS_RESET_CMD);
+    bypass_program(8, 0x55AA); /* Should fail. */
+    g_assert_cmphex(flash_read(0), ==, 0x0123);
+    g_assert_cmphex(flash_read(2), ==, 0x4567);
+    g_assert_cmphex(flash_read(4), ==, 0x89AB);
+    g_assert_cmphex(flash_read(6), ==, 0xCDEF);
+    g_assert_cmphex(flash_read(8), ==, 0xFFFF);
+
+    qtest_quit(global_qtest);
+}
+
+static void cleanup(void *opaque)
+{
+    unlink(image_path);
+}
+
+int main(int argc, char **argv)
+{
+    int fd = mkstemp(image_path);
+    if (fd == -1) {
+        g_printerr("Failed to create temporary file %s: %s\n", image_path,
+                   strerror(errno));
+        exit(EXIT_FAILURE);
+    }
+    if (ftruncate(fd, 8 * 1024 * 1024) < 0) {
+        int error_code = errno;
+        close(fd);
+        unlink(image_path);
+        g_printerr("Failed to truncate file %s to 8 MB: %s\n", image_path,
+                   strerror(error_code));
+        exit(EXIT_FAILURE);
+    }
+    close(fd);
+
+    qtest_add_abrt_handler(cleanup, NULL);
+    g_test_init(&argc, &argv, NULL);
+    qtest_add_func("pflash-cfi02", test_flash);
+    int result = g_test_run();
+    cleanup(NULL);
+    return result;
+}