From 88c3bb49e1bf2b808cbad1fbdeda09480ae580a7 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Sat, 9 Mar 2019 21:58:09 +0100 Subject: [PATCH] ddr: socfpga: Clean up ddr_setup() Replace the current rather convoluted code using ad-hoc polling mechanism with a more straightforward code. Use wait_for_bit_le32() to poll the DDRCALSTAT register instead of local reimplementation. It makes no sense to pull for 5 seconds before giving up and trying to restart the EMIF, so instead wait 500 mSec for the calibration to complete and if this fails, restart the EMIF and try again. Perform this 32 times instead of 3 times as the original code did. Signed-off-by: Marek Vasut Cc: Chin Liang See Cc: Dinh Nguyen Cc: Simon Goldschmidt Cc: Tien Fong Chee --- drivers/ddr/altera/sdram_arria10.c | 43 +++++++++++------------------- 1 file changed, 15 insertions(+), 28 deletions(-) diff --git a/drivers/ddr/altera/sdram_arria10.c b/drivers/ddr/altera/sdram_arria10.c index ff83c61002..1777e7e1a5 100644 --- a/drivers/ddr/altera/sdram_arria10.c +++ b/drivers/ddr/altera/sdram_arria10.c @@ -102,12 +102,6 @@ static int match_ddr_conf(u32 ddr_conf) return 0; } -/* Check whether SDRAM is successfully Calibrated */ -static int is_sdram_cal_success(void) -{ - return readl(&socfpga_ecc_hmc_base->ddrcalstat); -} - static int emif_clear(void) { writel(0, DDR_REG_CORE2SEQ); @@ -167,30 +161,23 @@ static int emif_reset(void) static int ddr_setup(void) { - int i, j, ddr_setup_complete = 0; - - /* Try 3 times to do a calibration */ - for (i = 0; (i < 3) && !ddr_setup_complete; i++) { - WATCHDOG_RESET(); - - /* A delay to wait for calibration bit to set */ - for (j = 0; (j < 10) && !ddr_setup_complete; j++) { - mdelay(500); - ddr_setup_complete = is_sdram_cal_success(); - } - - if (!ddr_setup_complete) - if (emif_reset()) - puts("Error: Failed to reset EMIF\n"); + int i, ret; + + /* Try 32 times to do a calibration */ + for (i = 0; i < 32; i++) { + mdelay(500); + ret = wait_for_bit_le32(&socfpga_ecc_hmc_base->ddrcalstat, + BIT(0), true, 500, false); + if (!ret) + return 0; + + ret = emif_reset(); + if (ret) + puts("Error: Failed to reset EMIF\n"); } - /* After 3 times trying calibration */ - if (!ddr_setup_complete) { - puts("Error: Could Not Calibrate SDRAM\n"); - return -EPERM; - } - - return 0; + puts("Error: Could Not Calibrate SDRAM\n"); + return -EPERM; } static int sdram_is_ecc_enabled(void) -- 2.25.1