Vignesh Raghavendra | c2dfd0a | 2019-10-23 13:30:01 +0530 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | // |
| 3 | // Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/ |
| 4 | // Author: Vignesh Raghavendra <vigneshr@ti.com> |
| 5 | |
| 6 | #include <common.h> |
| 7 | #include <asm/io.h> |
| 8 | #include <dm.h> |
| 9 | #include <regmap.h> |
| 10 | #include <syscon.h> |
| 11 | |
| 12 | #define FSS_SYSC_REG 0x4 |
| 13 | |
| 14 | #define HYPERBUS_CALIB_COUNT 25 |
| 15 | |
| 16 | struct am654_hbmc_priv { |
| 17 | void __iomem *mmiobase; |
| 18 | bool calibrated; |
| 19 | }; |
| 20 | |
| 21 | /* Calibrate by looking for "QRY" string within the CFI space */ |
| 22 | static int am654_hyperbus_calibrate(struct udevice *dev) |
| 23 | { |
| 24 | struct am654_hbmc_priv *priv = dev_get_priv(dev); |
| 25 | int count = HYPERBUS_CALIB_COUNT; |
| 26 | int pass_count = 0; |
| 27 | u16 qry[3]; |
| 28 | |
| 29 | if (priv->calibrated) |
| 30 | return 0; |
| 31 | |
| 32 | writew(0xF0, priv->mmiobase); |
| 33 | writew(0x98, priv->mmiobase + 0xaa); |
| 34 | |
| 35 | while (count--) { |
| 36 | qry[0] = readw(priv->mmiobase + 0x20); |
| 37 | qry[1] = readw(priv->mmiobase + 0x22); |
| 38 | qry[2] = readw(priv->mmiobase + 0x24); |
| 39 | |
| 40 | if (qry[0] == 'Q' && qry[1] == 'R' && qry[2] == 'Y') |
| 41 | pass_count++; |
| 42 | else |
| 43 | pass_count = 0; |
| 44 | if (pass_count == 5) |
| 45 | break; |
| 46 | } |
| 47 | writew(0xF0, priv->mmiobase); |
| 48 | writew(0xFF, priv->mmiobase); |
| 49 | |
| 50 | return pass_count == 5; |
| 51 | } |
| 52 | |
| 53 | static int am654_select_hbmc(struct udevice *dev) |
| 54 | { |
| 55 | struct regmap *regmap = syscon_get_regmap(dev_get_parent(dev)); |
| 56 | |
| 57 | return regmap_update_bits(regmap, FSS_SYSC_REG, 0x2, 0x2); |
| 58 | } |
| 59 | |
| 60 | static int am654_hbmc_bind(struct udevice *dev) |
| 61 | { |
| 62 | return dm_scan_fdt_dev(dev); |
| 63 | } |
| 64 | |
| 65 | static int am654_hbmc_probe(struct udevice *dev) |
| 66 | { |
| 67 | struct am654_hbmc_priv *priv = dev_get_priv(dev); |
| 68 | int ret; |
| 69 | |
| 70 | priv->mmiobase = devfdt_remap_addr_index(dev, 1); |
| 71 | if (dev_read_bool(dev, "mux-controls")) { |
| 72 | ret = am654_select_hbmc(dev); |
| 73 | if (ret) { |
| 74 | dev_err(dev, "Failed to select HBMC mux\n"); |
| 75 | return ret; |
| 76 | } |
| 77 | } |
| 78 | |
| 79 | if (!priv->calibrated) { |
| 80 | ret = am654_hyperbus_calibrate(dev); |
| 81 | if (!ret) { |
| 82 | dev_err(dev, "Calibration Failed\n"); |
| 83 | return -EIO; |
| 84 | } |
| 85 | } |
| 86 | priv->calibrated = true; |
| 87 | |
| 88 | return 0; |
| 89 | } |
| 90 | |
| 91 | static const struct udevice_id am654_hbmc_dt_ids[] = { |
| 92 | { |
| 93 | .compatible = "ti,am654-hbmc", |
| 94 | }, |
| 95 | { /* end of table */ } |
| 96 | }; |
| 97 | |
| 98 | U_BOOT_DRIVER(hbmc_am654) = { |
| 99 | .name = "hbmc-am654", |
| 100 | .id = UCLASS_MTD, |
| 101 | .of_match = am654_hbmc_dt_ids, |
| 102 | .probe = am654_hbmc_probe, |
| 103 | .bind = am654_hbmc_bind, |
| 104 | .priv_auto_alloc_size = sizeof(struct am654_hbmc_priv), |
| 105 | }; |