refactor(gpt): productize and refactor GPT library

This patch updates and refactors the GPT library and fixes bugs.

- Support all combinations of PGS, PPS, and L0GPTSZ parameters.
- PPS and PGS are set at runtime, L0GPTSZ is read from GPCCR_EL3.
- Use compiler definitions to simplify code.
- Renaming functions to better suit intended uses.
- MMU enabled before GPT APIs called.
- Add comments to make function usage more clear in GPT library.
- Added _rme suffix to file names to differentiate better from the
  GPT file system code.
- Renamed gpt_defs.h to gpt_rme_private.h to better separate private
  and public code.
- Renamed gpt_core.c to gpt_rme.c to better conform to TF-A precedent.

Signed-off-by: John Powell <john.powell@arm.com>
Change-Id: I4cbb23b0f81e697baa9fb23ba458aa3f7d1ed919

1 files changed, 228 insertions, 0 deletions

diff --git a/lib/gpt_rme/gpt_rme_private.h b/lib/gpt_rme/gpt_rme_private.h
new file mode 100644
index 000000000..5770bf7d6
--- /dev/null
+++ b/lib/gpt_rme/gpt_rme_private.h
@@ -0,0 +1,228 @@
+/*
+ * Copyright (c) 2021, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef GPT_RME_PRIVATE_H
+#define GPT_RME_PRIVATE_H
+
+#include <arch.h>
+#include <lib/gpt_rme/gpt_rme.h>
+#include <lib/utils_def.h>
+
+/******************************************************************************/
+/* GPT descriptor definitions                                                 */
+/******************************************************************************/
+
+/* GPT level 0 descriptor bit definitions. */
+#define GPT_L0_TYPE_MASK		UL(0xF)
+#define GPT_L0_TYPE_SHIFT		U(0)
+
+/* For now, we don't support contiguous descriptors, only table and block. */
+#define GPT_L0_TYPE_TBL_DESC		UL(0x3)
+#define GPT_L0_TYPE_BLK_DESC		UL(0x1)
+
+#define GPT_L0_TBL_DESC_L1ADDR_MASK	UL(0xFFFFFFFFFF)
+#define GPT_L0_TBL_DESC_L1ADDR_SHIFT	U(12)
+
+#define GPT_L0_BLK_DESC_GPI_MASK	UL(0xF)
+#define GPT_L0_BLK_DESC_GPI_SHIFT	U(4)
+
+/* GPT level 1 descriptor bit definitions */
+#define GPT_L1_GRAN_DESC_GPI_MASK	UL(0xF)
+
+/*
+ * This macro fills out every GPI entry in a granules descriptor to the same
+ * value.
+ */
+#define GPT_BUILD_L1_DESC(_gpi)		(((uint64_t)(_gpi) << 4*0) | \
+					 ((uint64_t)(_gpi) << 4*1) | \
+					 ((uint64_t)(_gpi) << 4*2) | \
+					 ((uint64_t)(_gpi) << 4*3) | \
+					 ((uint64_t)(_gpi) << 4*4) | \
+					 ((uint64_t)(_gpi) << 4*5) | \
+					 ((uint64_t)(_gpi) << 4*6) | \
+					 ((uint64_t)(_gpi) << 4*7) | \
+					 ((uint64_t)(_gpi) << 4*8) | \
+					 ((uint64_t)(_gpi) << 4*9) | \
+					 ((uint64_t)(_gpi) << 4*10) | \
+					 ((uint64_t)(_gpi) << 4*11) | \
+					 ((uint64_t)(_gpi) << 4*12) | \
+					 ((uint64_t)(_gpi) << 4*13) | \
+					 ((uint64_t)(_gpi) << 4*14) | \
+					 ((uint64_t)(_gpi) << 4*15))
+
+/******************************************************************************/
+/* GPT platform configuration                                                 */
+/******************************************************************************/
+
+/* This value comes from GPCCR_EL3 so no externally supplied definition. */
+#define GPT_L0GPTSZ		((unsigned int)((read_gpccr_el3() >> \
+				GPCCR_L0GPTSZ_SHIFT) & GPCCR_L0GPTSZ_MASK))
+
+/* The "S" value is directly related to L0GPTSZ */
+#define GPT_S_VAL		(GPT_L0GPTSZ + 30U)
+
+/*
+ * Map PPS values to T values.
+ *
+ *   PPS    Size    T
+ *   0b000  4GB     32
+ *   0b001  64GB    36
+ *   0b010  1TB     40
+ *   0b011  4TB     42
+ *   0b100  16TB    44
+ *   0b101  256TB   48
+ *   0b110  4PB     52
+ *
+ * See section 15.1.27 of the RME specification.
+ */
+typedef enum {
+	PPS_4GB_T =	32U,
+	PPS_64GB_T =	36U,
+	PPS_1TB_T =	40U,
+	PPS_4TB_T =	42U,
+	PPS_16TB_T =	44U,
+	PPS_256TB_T =	48U,
+	PPS_4PB_T =	52U
+} gpt_t_val_e;
+
+/*
+ * Map PGS values to P values.
+ *
+ *   PGS    Size    P
+ *   0b00   4KB     12
+ *   0b10   16KB    14
+ *   0b01   64KB    16
+ *
+ * Note that pgs=0b10 is 16KB and pgs=0b01 is 64KB, this is not a typo.
+ *
+ * See section 15.1.27 of the RME specification.
+ */
+typedef enum {
+	PGS_4KB_P =	12U,
+	PGS_16KB_P =	14U,
+	PGS_64KB_P =	16U
+} gpt_p_val_e;
+
+/* Max valid value for PGS. */
+#define GPT_PGS_MAX			(2U)
+
+/* Max valid value for PPS. */
+#define GPT_PPS_MAX			(6U)
+
+/******************************************************************************/
+/* L0 address attribute macros                                                */
+/******************************************************************************/
+
+/*
+ * If S is greater than or equal to T then there is a single L0 region covering
+ * the entire protected space so there is no L0 index, so the width (and the
+ * derivative mask value) are both zero.  If we don't specifically handle this
+ * special case we'll get a negative width value which does not make sense and
+ * could cause a lot of problems.
+ */
+#define GPT_L0_IDX_WIDTH(_t)		(((_t) > GPT_S_VAL) ? \
+					((_t) - GPT_S_VAL) : (0U))
+
+/* Bit shift for the L0 index field in a PA. */
+#define GPT_L0_IDX_SHIFT		(GPT_S_VAL)
+
+/* Mask for the L0 index field, must be shifted. */
+#define GPT_L0_IDX_MASK(_t)		(0xFFFFFFFFFFFFFFFFUL >> \
+					(64U - (GPT_L0_IDX_WIDTH(_t))))
+
+/* Total number of L0 regions. */
+#define GPT_L0_REGION_COUNT(_t)		((GPT_L0_IDX_MASK(_t)) + 1U)
+
+/* Total size of each GPT L0 region in bytes. */
+#define GPT_L0_REGION_SIZE		(1UL << (GPT_L0_IDX_SHIFT))
+
+/* Total size in bytes of the whole L0 table. */
+#define GPT_L0_TABLE_SIZE(_t)		((GPT_L0_REGION_COUNT(_t)) << 3U)
+
+/******************************************************************************/
+/* L1 address attribute macros                                                */
+/******************************************************************************/
+
+/* Width of the L1 index field. */
+#define GPT_L1_IDX_WIDTH(_p)		((GPT_S_VAL - 1U) - ((_p) + 3U))
+
+/* Bit shift for the L1 index field. */
+#define GPT_L1_IDX_SHIFT(_p)		((_p) + 4U)
+
+/* Mask for the L1 index field, must be shifted. */
+#define GPT_L1_IDX_MASK(_p)		(0xFFFFFFFFFFFFFFFFUL >> \
+					(64U - (GPT_L1_IDX_WIDTH(_p))))
+
+/* Bit shift for the index of the L1 GPI in a PA. */
+#define GPT_L1_GPI_IDX_SHIFT(_p)	(_p)
+
+/* Mask for the index of the L1 GPI in a PA. */
+#define GPT_L1_GPI_IDX_MASK		(0xF)
+
+/* Total number of entries in each L1 table. */
+#define GPT_L1_ENTRY_COUNT(_p)		((GPT_L1_IDX_MASK(_p)) + 1U)
+
+/* Total size in bytes of each L1 table. */
+#define GPT_L1_TABLE_SIZE(_p)		((GPT_L1_ENTRY_COUNT(_p)) << 3U)
+
+/******************************************************************************/
+/* General helper macros                                                      */
+/******************************************************************************/
+
+/* Protected space actual size in bytes. */
+#define GPT_PPS_ACTUAL_SIZE(_t)	(1UL << (_t))
+
+/* Granule actual size in bytes. */
+#define GPT_PGS_ACTUAL_SIZE(_p)	(1UL << (_p))
+
+/* L0 GPT region size in bytes. */
+#define GPT_L0GPTSZ_ACTUAL_SIZE	(1UL << GPT_S_VAL)
+
+/* Get the index of the L0 entry from a physical address. */
+#define GPT_L0_IDX(_pa)		((_pa) >> GPT_L0_IDX_SHIFT)
+
+/*
+ * This definition is used to determine if a physical address lies on an L0
+ * region boundary.
+ */
+#define GPT_IS_L0_ALIGNED(_pa)	(((_pa) & (GPT_L0_REGION_SIZE - U(1))) == U(0))
+
+/* Get the type field from an L0 descriptor. */
+#define GPT_L0_TYPE(_desc)	(((_desc) >> GPT_L0_TYPE_SHIFT) & \
+				GPT_L0_TYPE_MASK)
+
+/* Create an L0 block descriptor. */
+#define GPT_L0_BLK_DESC(_gpi)	(GPT_L0_TYPE_BLK_DESC | \
+				(((_gpi) & GPT_L0_BLK_DESC_GPI_MASK) << \
+				GPT_L0_BLK_DESC_GPI_SHIFT))
+
+/* Create an L0 table descriptor with an L1 table address. */
+#define GPT_L0_TBL_DESC(_pa)	(GPT_L0_TYPE_TBL_DESC | ((uint64_t)(_pa) & \
+				(GPT_L0_TBL_DESC_L1ADDR_MASK << \
+				GPT_L0_TBL_DESC_L1ADDR_SHIFT)))
+
+/* Get the GPI from an L0 block descriptor. */
+#define GPT_L0_BLKD_GPI(_desc)	(((_desc) >> GPT_L0_BLK_DESC_GPI_SHIFT) & \
+				GPT_L0_BLK_DESC_GPI_MASK)
+
+/* Get the L1 address from an L0 table descriptor. */
+#define GPT_L0_TBLD_ADDR(_desc)	((uint64_t *)(((_desc) & \
+				(GPT_L0_TBL_DESC_L1ADDR_MASK << \
+				GPT_L0_TBL_DESC_L1ADDR_SHIFT))))
+
+/* Get the index into the L1 table from a physical address. */
+#define GPT_L1_IDX(_p, _pa)	(((_pa) >> GPT_L1_IDX_SHIFT(_p)) & \
+				GPT_L1_IDX_MASK(_p))
+
+/* Get the index of the GPI within an L1 table entry from a physical address. */
+#define GPT_L1_GPI_IDX(_p, _pa)	(((_pa) >> GPT_L1_GPI_IDX_SHIFT(_p)) & \
+				GPT_L1_GPI_IDX_MASK)
+
+/* Determine if an address is granule-aligned. */
+#define GPT_IS_L1_ALIGNED(_p, _pa) (((_pa) & (GPT_PGS_ACTUAL_SIZE(_p) - U(1))) \
+				   == U(0))
+
+#endif /* GPT_RME_PRIVATE_H */